chore: Update CHANGELOG.md

Update CHANGELOG.md to document the header visibility change.

Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>

Author: RuoqingHe

CHANGELOG.md

@@ -1,8 +1,12 @@
 # Upcoming Release
+
 ## Changed
 - [[#148](https://github.com/rust-vmm/linux-loader/pull/148)] Fixing kernel commandline parameter validation
   This change allows parameter values containing spaces in the middle, provided they are enclosed in quotes. However, 
   strings with quotes in the middle will no longer be accepted as valid parameter values.
+- [[#205](https://github.com/rust-vmm/linux-loader/pull/205)] Make image header for ARM and RISC-V public
+  Kernel headers for ARM and RISC-V are made public to be used in a fw_cfg
+  implementation that reads the kernel header.
 
 # [v0.13.0]