ARM: 9211/1: domain: drop modify_domain()

This function/macro isn't used anywhere in the kernel.
The only user was set_fs() and was deleted in the set_fs()
removal patch set.

Fixes: 8ac6f5d7 ("ARM: 9113/1: uaccess: remove set_fs() implementation")
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

arch/arm/include/asm/domain.h

@@ -112,19 +112,6 @@ static __always_inline void set_domain(unsigned int val)
 }
 #endif
 
-#ifdef CONFIG_CPU_USE_DOMAINS
-#define modify_domain(dom,type)					\
-	do {							\
-		unsigned int domain = get_domain();		\
-		domain &= ~domain_mask(dom);			\
-		domain = domain | domain_val(dom, type);	\
-		set_domain(domain);				\
-	} while (0)
-
-#else
-static inline void modify_domain(unsigned dom, unsigned type)	{ }
-#endif
-
 /*
  * Generate the T (user) versions of the LDR/STR and related
  * instructions (inline assembly)