bitops: protect find_first_{,zero}_bit properly

find_first_bit() and find_first_zero_bit() are not protected with
ifdefs as other functions in find.h. It causes build errors on some
platforms if CONFIG_GENERIC_FIND_FIRST_BIT is enabled.
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Fixes: 2cc7b6a4 ("lib: add fast path for find_first_*_bit() and find_last_bit()")
Reported-by: kernel test robot <lkp@intel.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

include/asm-generic/bitops/find.h

@@ -97,6 +97,7 @@ unsigned long find_next_zero_bit(const unsigned long *addr, unsigned long size,
 
 #ifdef CONFIG_GENERIC_FIND_FIRST_BIT
 
+#ifndef find_first_bit
 /**
  * find_first_bit - find the first set bit in a memory region
  * @addr: The address to start the search at
@@ -116,7 +117,9 @@ unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
 
 	return _find_first_bit(addr, size);
 }
+#endif
 
+#ifndef find_first_zero_bit
 /**
  * find_first_zero_bit - find the first cleared bit in a memory region
  * @addr: The address to start the search at
@@ -136,6 +139,8 @@ unsigned long find_first_zero_bit(const unsigned long *addr, unsigned long size)
 
 	return _find_first_zero_bit(addr, size);
 }
+#endif
+
 #else /* CONFIG_GENERIC_FIND_FIRST_BIT */
 
 #ifndef find_first_bit