Since commit 
12a0ef7b0ac3 ("arm64: use generic strnlen_user and
strncpy_from_user functions"), the definition of __addr_ok() has been
languishing unused; eradicate the sucker.
CC: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
 
 #define segment_eq(a, b)       ((a) == (b))
 
-/*
- * Return 1 if addr < current->addr_limit, 0 otherwise.
- */
-#define __addr_ok(addr)                                                        \
-({                                                                     \
-       unsigned long flag;                                             \
-       asm("cmp %1, %0; cset %0, lo"                                   \
-               : "=&r" (flag)                                          \
-               : "r" (addr), "0" (current_thread_info()->addr_limit)   \
-               : "cc");                                                \
-       flag;                                                           \
-})
-
 /*
  * Test whether a block of memory is a valid user space address.
  * Returns 1 if the range is valid, 0 otherwise.