SPM: Rename files for consistency

Rename files prefixed by sp_ to spm_.

Change-Id: Ie3016a4c4ac5987fe6fdd734c6b470c60954e23d
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
diff --git a/services/std_svc/spm/spm.mk b/services/std_svc/spm/spm.mk
index b52292d..4ba9feb 100644
--- a/services/std_svc/spm/spm.mk
+++ b/services/std_svc/spm/spm.mk
@@ -16,11 +16,11 @@
 SPM_SOURCES	:=	$(addprefix services/std_svc/spm/,	\
 			${ARCH}/spm_helpers.S			\
 			${ARCH}/spm_shim_exceptions.S		\
-			sp_setup.c				\
-			sp_xlat.c				\
 			spci.c					\
 			spm_buffers.c				\
 			spm_main.c				\
+			spm_setup.c				\
+			spm_xlat.c				\
 			sprt.c)					\
 			${SPRT_LIB_SOURCES}