Fix MISRA Rule 5.3 Part 5

Use a _ prefix for macro arguments to prevent that argument from
hiding variables of the same name in the outer scope

Rule 5.3: An identifier declared in an inner scope shall not
          hide an identifier declared in an outer scope

Fixed For:
    make LOG_LEVEL=50 PLAT=juno

Change-Id: I575fbc96e8267f2b075e88def1f6e3185394613a
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>
diff --git a/plat/arm/css/drivers/sds/sds_private.h b/plat/arm/css/drivers/sds/sds_private.h
index 649576b..43b97f6 100644
--- a/plat/arm/css/drivers/sds/sds_private.h
+++ b/plat/arm/css/drivers/sds/sds_private.h
@@ -67,18 +67,18 @@
 	uint32_t reg[2];
 } struct_header_t;
 
-#define GET_SDS_HEADER_ID(header)			\
-	((((struct_header_t *)(header))->reg[0]) & SDS_HEADER_ID_MASK)
-#define GET_SDS_HEADER_VERSION(header)			\
-	(((((struct_header_t *)(header))->reg[0]) >> SDS_HEADER_MINOR_VERSION_SHIFT)\
+#define GET_SDS_HEADER_ID(_header)			\
+	((((struct_header_t *)(_header))->reg[0]) & SDS_HEADER_ID_MASK)
+#define GET_SDS_HEADER_VERSION(_header)			\
+	(((((struct_header_t *)(_header))->reg[0]) >> SDS_HEADER_MINOR_VERSION_SHIFT)\
 	& SDS_HEADER_VERSION_MASK)
-#define GET_SDS_HEADER_STRUCT_SIZE(header)		\
-	(((((struct_header_t *)(header))->reg[1]) >> SDS_HEADER_STRUCT_SIZE_SHIFT)\
+#define GET_SDS_HEADER_STRUCT_SIZE(_header)		\
+	(((((struct_header_t *)(_header))->reg[1]) >> SDS_HEADER_STRUCT_SIZE_SHIFT)\
 	& SDS_HEADER_STRUCT_SIZE_MASK)
-#define IS_SDS_HEADER_VALID(header)			\
-	((((struct_header_t *)(header))->reg[1]) & SDS_HEADER_VALID_MASK)
-#define GET_SDS_STRUCT_FIELD(header, field_offset)	\
-	((((uint8_t *)(header)) + sizeof(struct_header_t)) + (field_offset))
+#define IS_SDS_HEADER_VALID(_header)			\
+	((((struct_header_t *)(_header))->reg[1]) & SDS_HEADER_VALID_MASK)
+#define GET_SDS_STRUCT_FIELD(_header, _field_offset)	\
+	((((uint8_t *)(_header)) + sizeof(struct_header_t)) + (_field_offset))
 
 /* Region Descriptor describing the SDS Memory Region */
 typedef struct region_descriptor {