flashrom: Add support for ARC platform

Signed-off-by: Rosen Penev <rosenp@gmail.com>
Change-Id: I88cbe74b716d5fab16133fbf2ce9c35b74c25f32
Reviewed-on: https://review.coreboot.org/c/flashrom/+/35831
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: David Hendricks <david.hendricks@gmail.com>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/platform.h b/platform.h
index d290afc..751957c 100644
--- a/platform.h
+++ b/platform.h
@@ -74,9 +74,12 @@
 #elif defined(__s390__) || defined(__s390x__) || defined(__zarch__)
 	#define __FLASHROM_ARCH__ "s390"
 	#define IS_S390 1
+#elif defined(__arc__)
+	#define __FLASHROM_ARCH__ "arc"
+	#define IS_ARC 1
 #endif
 
-#if !(IS_X86 || IS_MIPS || IS_PPC || IS_ARM || IS_SPARC || IS_ALPHA || IS_HPPA || IS_M68K || IS_RISCV || IS_SH || IS_S390)
+#if !(IS_X86 || IS_MIPS || IS_PPC || IS_ARM || IS_SPARC || IS_ALPHA || IS_HPPA || IS_M68K || IS_RISCV || IS_SH || IS_S390 || IS_ARC)
 #error Unknown architecture
 #endif
 
@@ -123,6 +126,13 @@
 /* SPARC is big endian in general (but allows to access data in little endian too). */
 #define __FLASHROM_BIG_ENDIAN__ 1
 
+#elif IS_ARC
+#if defined(__BIG_ENDIAN__)
+#define __FLASHROM_BIG_ENDIAN__ 1
+#else
+#define __FLASHROM_LITTLE_ENDIAN__ 1
+#endif
+
 #endif /* IS_? */
 
 #if !defined (__FLASHROM_BIG_ENDIAN__) && !defined (__FLASHROM_LITTLE_ENDIAN__)