feat(security): Generalize boot flow page for non-AM64x SoCs

Currently, the secure boot section is tailored for AM64x. But the same
information is applicable to non-AM64x SoCs, that is AM62x, AM62P. Therefore
generalize the page and add it these other devices' TOCs.

Signed-off-by: Suhaas Joshi <s-joshi@ti.com>

Author: jsuhaas22

configs/AM62PX/AM62PX_linux_toc.txt

@@ -103,6 +103,7 @@ linux/Foundational_Components/System_Security/Security_overview
 linux/Foundational_Components/System_Security/SELinux
 linux/Foundational_Components/System_Security/Auth_boot
 linux/Foundational_Components/System_Security/Memory_Firewalls
+linux/Foundational_Components_Secure_Boot
 
 linux/Foundational_Components_Kernel_Users_Guide
 linux/Foundational_Components_Kernel_LTP-DDT_Validation

configs/AM62X/AM62X_linux_toc.txt

@@ -100,6 +100,7 @@ linux/Foundational_Components/System_Security/Security_overview
 linux/Foundational_Components/System_Security/SELinux
 linux/Foundational_Components/System_Security/Auth_boot
 linux/Foundational_Components/System_Security/Memory_Firewalls
+linux/Foundational_Components_Secure_Boot
 
 linux/Foundational_Components_PRU_Subsystem
 linux/Foundational_Components/PRU-ICSS-Linux-Drivers

source/linux/Foundational_Components_Secure_Boot.rst

@@ -69,14 +69,20 @@ The exact location is device dependent. More details can be found in the device
     * DMSC firmware: `Texas Instruments Foundational Security (TIFS)` + Device/Power Manager: After authentication/decryption, DMSC firmware replaces the Secure ROM as the authenticator entity executing on the DMSC core.
     * R5 SPL: The R5 SPL bootloader is executed on the R5 core.
 
-.. ifconfig:: CONFIG_part_variant in ('AM62x')
+.. ifconfig:: CONFIG_part_variant not in ('AM64X')
 
-    - `AM62x TRM <https://www.ti.com/lit/pdf/spruiv7>`_
+   .. ifconfig:: CONFIG_part_variant in ('AM62X')
 
-    The contents of this first stage image are authenticated and decrypted by the Secure ROM. Contents include:
+       - `AM62x TRM <https://www.ti.com/lit/pdf/spruiv7>`_
+
+   .. ifconfig:: CONFIG_part_variant in ('AM62PX')
+
+      - `AM62P TRM <https://www.ti.com/lit/pdf/spruj83>`_
+
+   The contents of this first stage image are authenticated and decrypted by the Secure ROM. Contents include:
 
-    * `Texas Instruments Foundational Security (TIFS)` firmware: After authentication/decryption, TIFS firmware replaces the Secure ROM as the authenticator entity executing on the TIFS core.
-    * R5 SPL`: The R5 SPL bootloader is executed on the R5 core.
+   * `Texas Instruments Foundational Security (TIFS)` firmware: After authentication/decryption, TIFS firmware replaces the Secure ROM as the authenticator entity executing on the TIFS core.
+   * R5 SPL`: The R5 SPL bootloader is executed on the R5 core.
 
 .. rubric:: R5 SPL
 
@@ -195,9 +201,9 @@ HS Boot Flow Tools
 
 U-boot:
 
-    The ti-u-boot source is a project used to create tiboot3.bin, tispl.bin, and u-boot.img. To create  tiboot3.bin for AM64x family devices, u-boot builds R5 SPL and
+    The ti-u-boot source is a project used to create tiboot3.bin, tispl.bin, and u-boot.img. To create  tiboot3.bin for Sitara family devices, u-boot builds R5 SPL and
     binman packages it in a `tiboot3.bin` image. To build A53 SPL, binman takes ATF (bl31.bin), OPTEE (bl32.bin), A53 SPL, and A53 DTBs and packages
-    them in a `tispl.bin` image. The openssl library can then then be used to sign each component as specified in k3-am64x-binman.dtsi.
+    them in a `tispl.bin` image. The openssl library can then then be used to sign each component as specified in k3-<soc>-binman.dtsi.
 
     .. code-block:: console
 
@@ -246,7 +252,7 @@ OPTEE:
 Ti-linux-firmware:
 
     The ti-linux-firmware is a TI repository where all firmware releases are stored. Firmwares for a device family can also be found in the pre-built SDK
-    under <path-to-tisdk>/board-support/prebuilt-images/am64xx-evm. Binman expects to find the device firmware with the following appended to u-boot build command:
+    under <path-to-tisdk>/board-support/prebuilt-images/<evm>. Binman expects to find the device firmware with the following appended to u-boot build command:
     BINMAN_INDIRS=<path-to-tisdk>/board-support/prebuilt-images, and expects to find a ti-sysfw directory in this path.
 
     .. code-block:: console