[PATCH][Testsuite]Use user defined memmove in gcc.c-torture/execute/builtins/memops...

[PATCH][Testsuite]Use user defined memmove in gcc.c-torture/execute/builtins/memops-asm-lib.c

After the change r249278. bcopy is folded into memmove. And in newlib
aarch64 memmove implementation, it will call memcpy in certain conditions.
The memcpy defined in memops-asm-lib.c will abort when the test is running.

A user defined memmove function is defined to bypass the library one.
So that memcpy won't be called accidentally.

gcc/testsuite/

	* gcc.c-torture/execute/builtins/memops-asm-lib.c (my_memmove): New.
	* gcc.c-torture/execute/builtins/memops-asm.c (memmove): Declare memmove.

Co-Authored-By: Szabolcs Nagy <szabolcs.nagy@arm.com>
From-SVN: r249647