Update libcpu/aarch64/common/cpu_gcc.S

Co-authored-by: Copilot <[email protected]>

Author: lygstate

libcpu/aarch64/common/cpu_gcc.S

@@ -122,7 +122,7 @@ rt_hw_get_cntpct_val:
  * get gtimer frq value
  * According to the document `Arm A-profile Architecture Registers:
  * CNTFRQ_EL0, Counter-timer Frequency Register`
- * Bits [63:32] is reserved, so only the lower 32 bits are take effect.
+ * Bits [63:32] are reserved, so only the lower 32 bits take effect.
  */
 .globl rt_hw_get_gtimer_frq
 rt_hw_get_gtimer_frq: