firmware: dmi: Add macro SMBIOS_ENTRY_POINT_SCAN_START

Use SMBIOS_ENTRY_POINT_SCAN_START instead of 0xF0000, because other
archtecture maybe use a special start address such as 0xFFFE000 for
Loongson platform.

Signed-off-by: Tiezhu Yang <[e-mail]>
Reviewed-by: Jean Delvare <[e-mail]>
Signed-off-by: Thomas Bogendoerfer <[e-mail]>

drivers/firmware/dmi_scan.c

···
 #include <asm/dmi.h>
 #include <asm/unaligned.h>
 
+#ifndef SMBIOS_ENTRY_POINT_SCAN_START
+#define SMBIOS_ENTRY_POINT_SCAN_START 0xF0000
+#endif
+
 struct kobject *dmi_kobj;
 EXPORT_SYMBOL_GPL(dmi_kobj);
 
···
 			return;
 		}
 	} else if (IS_ENABLED(CONFIG_DMI_SCAN_MACHINE_NON_EFI_FALLBACK)) {
-		p = dmi_early_remap(0xF0000, 0x10000);
+		p = dmi_early_remap(SMBIOS_ENTRY_POINT_SCAN_START, 0x10000);
 		if (p == NULL)
 			goto error;