stm32f103: add example config

Config based on the STM32F4 ditto.

Booting takes about 6 seconds and update around 15.

Signed-off-by: Patrik Dahlström <risca@dalakolonin.se>

Author: Risca

config/examples/stm32f103.config

@@ -0,0 +1,16 @@
+ARCH?=ARM
+TARGET?=stm32f103
+SIGN?=ED25519
+HASH?=SHA256
+VTOR?=0
+SPMATH?=1
+DISABLE_BACKUP=0
+# 13 KB bootloader partition
+# 2 * 25 KB application partitions
+# 1 KB swap partition
+# 64 KB total
+WOLFBOOT_PARTITION_BOOT_ADDRESS?=0x08003400
+WOLFBOOT_PARTITION_UPDATE_ADDRESS?=0x08009800
+WOLFBOOT_PARTITION_SWAP_ADDRESS?=0x0800FC00
+WOLFBOOT_PARTITION_SIZE?=0x6400
+WOLFBOOT_SECTOR_SIZE?=0x600