Fix Thumb-2 memcpy.

When an IT block was changed from having two instructions to having
one, the IT instruction at the start of the block was not updated,
causing memcpy to fail to assemble for Thumb-2; this patch makes the
obvious fix.

Signed-off-by: Joseph Myers <joseph@codesourcery.com>

libc/string/arm/_memcpy.S

@@ -108,7 +108,7 @@ _memcpy:
 	cmp	r1, r0
 	bcc	.Lmemcpy_backwards
 
-	IT(tt, eq)			/* Quick abort for src=dst */
+	IT(t, eq)			/* Quick abort for src=dst */
 #if defined(__USE_BX__)
         bxeq    lr
 #else