libc: Use printf and snprintf across codebase

tf_printf and tf_snprintf are now called printf and snprintf, so the
code needs to be updated.

Change-Id: Iffeee97afcd6328c4c2d30830d4923b964682d71
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/lib/pmf/pmf_main.c b/lib/pmf/pmf_main.c
index 0208948..a020860 100644
--- a/lib/pmf/pmf_main.c
+++ b/lib/pmf/pmf_main.c
@@ -178,7 +178,7 @@
  */
 void __pmf_dump_timestamp(unsigned int tid, unsigned long long ts)
 {
-	tf_printf("PMF:cpu %u	tid %u	ts %llu\n",
+	printf("PMF:cpu %u	tid %u	ts %llu\n",
 		plat_my_core_pos(), tid, ts);
 }