Remove locale-cancer from grep(1)

What in the actual fuck? Check the ml history on why we won't use
locale() functions in this context.
diff --git a/grep.c b/grep.c
index 22b3b6f..64ffbe2 100644
--- a/grep.c
+++ b/grep.c
@@ -1,5 +1,4 @@
 /* See LICENSE file for copyright and license details. */
-#include <locale.h>
 #include <regex.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -179,8 +178,6 @@
 	FILE *fp;
 	char *arg;
 
-	setlocale(LC_ALL, "");
-
 	SLIST_INIT(&phead);
 
 	ARGBEGIN {