Fork TF-A's libc

Create a fork of "Trusted Firmware-A" libc to be used by
trusted-services SWd components.

URL: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git
SHA: f2735ebccf5173f74c0458736ec526276106097e
Paths: trusted-firmware-a/lib/libc and trusted-firmware-a/include/lib/libc

Signed-off-by: Gabor Ambrus <gabor.ambrus@arm.com>
Signed-off-by: Imre Kis <imre.kis@arm.com>
Change-Id: I2f3b6cbf739265c4441fbba06ea6c9db339022c4
diff --git a/components/common/libc/src/memcmp.c b/components/common/libc/src/memcmp.c
new file mode 100644
index 0000000..db2701b
--- /dev/null
+++ b/components/common/libc/src/memcmp.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2013-2019, Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+#include <string.h>
+
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+	const unsigned char *s = s1;
+	const unsigned char *d = s2;
+	unsigned char sc;
+	unsigned char dc;
+
+	while (len--) {
+		sc = *s++;
+		dc = *d++;
+		if (sc - dc)
+			return (sc - dc);
+	}
+
+	return 0;
+}