plat/arm: Use `mov_imm` macro to load immediate values

This patch makes use of mov_imm macro where possible to load
immediate values within ARM platform layer.

Change-Id: I02bc7fbc1fa334c9fccf76fbddf515952f9a1298
Signed-off-by: Soby Mathew <soby.mathew@arm.com>
diff --git a/plat/arm/css/common/aarch64/css_helpers.S b/plat/arm/css/common/aarch64/css_helpers.S
index 59d9206..5096d8d 100644
--- a/plat/arm/css/common/aarch64/css_helpers.S
+++ b/plat/arm/css/common/aarch64/css_helpers.S
@@ -108,7 +108,7 @@
 func plat_is_my_cpu_primary
 	mov	x9, x30
 	bl	plat_my_core_pos
-	ldr	x1, =SCP_BOOT_CFG_ADDR
+	mov_imm	x1, SCP_BOOT_CFG_ADDR
 	ldr	x1, [x1]
 	ubfx	x1, x1, #PLAT_CSS_PRIMARY_CPU_SHIFT, \
 			#PLAT_CSS_PRIMARY_CPU_BIT_WIDTH