libc: Move tf_printf and tf_snprintf to libc

Change their names to printf and snprintf. They are much smaller than
the previous versions we had, which makes them better suited for the
Trusted Firmware.

Change-Id: Ia872af91b7b967c47fce012eccecede7873a3daf
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/lib/libc/libc.mk b/lib/libc/libc.mk
index 0dee4f5..554f36b 100644
--- a/lib/libc/libc.mk
+++ b/lib/libc/libc.mk
@@ -16,12 +16,12 @@
 			printf.c			\
 			putchar.c			\
 			puts.c				\
+			snprintf.c			\
 			strchr.c			\
 			strcmp.c			\
 			strlen.c			\
 			strncmp.c			\
-			strnlen.c			\
-			subr_prf.c)
+			strnlen.c)
 
 INCLUDES	+=	-Iinclude/lib/libc		\
 			-Iinclude/lib/libc/$(ARCH)	\