Use __inhibit_loop_to_libcall in all memset/memcpy implementations

This macro selects a compiler option that disables recognition of
common memset/memcpy patterns and converting those to direct
memset/memcpy calls.

Signed-off-by: Keith Packard <keithp@keithp.com>

newlib/libc/machine/riscv/memcpy.c

@@ -11,10 +11,12 @@
 
 #include <string.h>
 #include <stdint.h>
+#include "../../string/local.h"
 
 #define unlikely(X) __builtin_expect (!!(X), 0)
 
 void *
+__inhibit_loop_to_libcall
 memcpy(void *__restrict aa, const void *__restrict bb, size_t n)
 {
   #define BODY(a, b, t) { \