user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

user/include/mlibc/tests/glibc/rpmatch.c

@@ -0,0 +1,17 @@
+#include <assert.h>
+#include <locale.h>
+#include <stdlib.h>
+
+int main() {
+	assert(rpmatch("y") == 1);
+	assert(rpmatch("Y") == 1);
+	assert(rpmatch("n") == 0);
+	assert(rpmatch("N") == 0);
+	assert(rpmatch("yno") == 1);
+	assert(rpmatch("no") == 0);
+	assert(rpmatch("NO") == 0);
+	assert(rpmatch("YES") == 1);
+	assert(rpmatch("mlibc") == -1);
+
+	return 0;
+}