imx: simplify dependency with SPL_BOOTROM_SUPPORT

For SoCs support ROM API, CONFIG_SPL_BOOTROM_SUPPORT is needed,
so use this macro to guard the code to avoid extend the list.

And drop the guard with structure definition, there is no need.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/include/asm/mach-imx/sys_proto.h b/arch/arm/include/asm/mach-imx/sys_proto.h
index fadb67d..3095214 100644
--- a/arch/arm/include/asm/mach-imx/sys_proto.h
+++ b/arch/arm/include/asm/mach-imx/sys_proto.h
@@ -146,7 +146,6 @@
 	u32 size; /* size of reg range */
 };
 
-#if defined(CONFIG_IMX8_ROMAPI)
 struct rom_api {
 	u16 ver;
 	u16 tag;
@@ -182,8 +181,6 @@
 u32 rom_api_download_image(u8 *dest, u32 offset, u32 size);
 u32 rom_api_query_boot_infor(u32 info_type, u32 *info);
 
-#endif
-
 /* For i.MX ULP */
 #define BT0CFG_LPBOOT_MASK	0x1
 #define BT0CFG_DUALBOOT_MASK	0x2
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 50f4c08..6b59752 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -170,7 +170,8 @@
 
 config SPL_IMX_ROMAPI_LOADADDR
 	hex "Default load address to load image through ROM API"
-	depends on IMX8_ROMAPI
+	depends on IMX8_ROMAPI || SPL_BOOTROM_SUPPORT
+	default 0
 
 config IMX_DCD_ADDR
 	hex "DCD Blocks location on the image"