plat/arm: move compile time switch from source to dt file

This will help in keeping source file generic and conditional
compilation can be contained in platform provided dt files.
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
Change-Id: I3c6e0a429073f0afb412b9ba521ce43f880b57fe

plat/arm/board/fvp/fdts/fvp_fw_config.dts

@@ -36,11 +36,14 @@
 			id = <SOC_FW_CONFIG_ID>;
 		};
 
+/* If required, SPD should enable loading of trusted OS fw config */
+#if defined(SPD_tspd) || defined(SPD_spmd)
 		tos_fw-config {
 			load-address = <0x0 0x04001500>;
 			max-size = <0xB00>;
 			id = <TOS_FW_CONFIG_ID>;
 		};
+#endif
 
 #if !defined(SPD_spmd)
 		nt_fw-config {

plat/arm/common/arm_dyn_cfg.c

@@ -208,10 +208,7 @@ void arm_bl2_dyn_cfg_init(void)
 			HW_CONFIG_ID,
 			SOC_FW_CONFIG_ID,
 			NT_FW_CONFIG_ID,
-#if defined(SPD_tspd) || defined(SPD_spmd)
-			/* tos_fw_config is only present for TSPD/SPMD */
 			TOS_FW_CONFIG_ID
-#endif
 	};
 
 	const struct dyn_cfg_dtb_info_t *dtb_info;