target: declare local symbols as static

Functions and variables that are not used outside the file should
be declared as static.

Change-Id: I9f97571a528f0cb3c3c26f873577ab16fdec3cdc
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5895
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

src/target/cortex_a.c

@@ -1115,7 +1115,8 @@ static int cortex_a_post_debug_entry(struct target *target)
 	return ERROR_OK;
 }
 
-int cortex_a_set_dscr_bits(struct target *target, unsigned long bit_mask, unsigned long value)
+static int cortex_a_set_dscr_bits(struct target *target,
+		unsigned long bit_mask, unsigned long value)
 {
 	struct armv7a_common *armv7a = target_to_armv7a(target);
 	uint32_t dscr;