arch: arm: core: aarch32: Updated brief file description

Updated brief file description so that it also mentions the aarch32
Cortex-A CPUs.

Signed-off-by: Immo Birnbaum <[email protected]>

Author: ibirnbaum

arch/arm/core/aarch32/cortex_a_r/reboot.c

@@ -6,7 +6,7 @@
 
 /**
  * @file
- * @brief ARM Cortex-R System Control Block interface
+ * @brief ARM Cortex-A and Cortex-R System Control Block interface
  */
 
 #include <kernel.h>