soc/riscv: Refactor the code for coding style. [1/4]

PD#SWPL-68240

Problem:
Refactor the code for coding style

Solution:
Refactor the code for coding style

Verify:
N/A

Change-Id: Ice836fb01287a444f9c5a2301609b60ac3edf3a2
Signed-off-by: xiaohu.huang <xiaohu.huang@amlogic.com>
diff --git a/n200_func.h b/n200_func.h
index 7928484..a76fc7f 100644
--- a/n200_func.h
+++ b/n200_func.h
@@ -11,6 +11,7 @@
 
 #include "n200_timer.h"
 #include "interrupt_control.h"
+#include "gcc_compiler_attributes.h"
 
 void pmp_open_all_space(void);
 
@@ -30,7 +31,7 @@
 
 uint32_t get_cpu_freq(void);
 
-uint32_t __attribute__((noinline)) measure_cpu_freq(size_t n);
+uint32_t __noinline measure_cpu_freq(size_t n);
 
 void wfe(void);