Rename BL33_BASE option to PRELOADED_BL33_BASE

To avoid confusion the build option BL33_BASE has been renamed to
PRELOADED_BL33_BASE, which is more descriptive of what it does and
doesn't get mistaken by similar names like BL32_BASE that work in a
completely different way.

NOTE: PLATFORMS USING BUILD OPTION `BL33_BASE` MUST CHANGE TO THE NEW
BUILD OPTION `PRELOADED_BL33_BASE`.

Change-Id: I658925ebe95406edf0325f15aa1752e1782aa45b
diff --git a/plat/arm/common/arm_bl31_setup.c b/plat/arm/common/arm_bl31_setup.c
index deb9612..8fcfa77 100644
--- a/plat/arm/common/arm_bl31_setup.c
+++ b/plat/arm/common/arm_bl31_setup.c
@@ -142,11 +142,11 @@
 	 * Tell BL31 where the non-trusted software image
 	 * is located and the entry state information
 	 */
-#ifdef BL33_BASE
-	bl33_image_ep_info.pc = BL33_BASE;
+#ifdef PRELOADED_BL33_BASE
+	bl33_image_ep_info.pc = PRELOADED_BL33_BASE;
 #else
 	bl33_image_ep_info.pc = plat_get_ns_image_entrypoint();
-#endif
+#endif /* PRELOADED_BL33_BASE */
 	bl33_image_ep_info.spsr = arm_get_spsr_for_bl33_entry();
 	SET_SECURITY_STATE(bl33_image_ep_info.h.attr, NON_SECURE);