fix(arm): correct the SPMC_AT_EL3 condition

Addressed the SPMC_AT_EL3 condition by using '#if' instead of
'#if defined'. This change is warranted because the SPMC_AT_EL3
option is always defined.

Change-Id: I76d9b8d502f452c58bc0040745d642cbe11dc8eb
Signed-off-by: Manish V Badarkhe <Manish.Badarkhe@arm.com>
diff --git a/plat/arm/common/arm_bl31_setup.c b/plat/arm/common/arm_bl31_setup.c
index 03e6889..8e90615 100644
--- a/plat/arm/common/arm_bl31_setup.c
+++ b/plat/arm/common/arm_bl31_setup.c
@@ -198,7 +198,7 @@
 	while (bl_params != NULL) {
 		if (bl_params->image_id == BL32_IMAGE_ID) {
 			bl32_image_ep_info = *bl_params->ep_info;
-#if defined(SPMC_AT_EL3)
+#if SPMC_AT_EL3
 			/*
 			 * Populate the BL32 image base, size and max limit in
 			 * the entry point information, since there is no