Cleanup: Fix build problems with the Intel compiler

fil_space_t::flush_low(): Define and declare without inline.

ut_is_2pow(): Remove UNIV_LIKELY. This is almost exclusively
used in debug assertions. UNIV_LIKELY is not compatible with
static_assert in some compilers.

storage/innobase/fil/fil0fil.cc

@@ -492,7 +492,7 @@ void fil_node_t::prepare_to_close_or_detach()
 }
 
 /** Flush any writes cached by the file system. */
-inline void fil_space_t::flush_low()
+void fil_space_t::flush_low()
 {
   ut_ad(!mutex_own(&fil_system.mutex));
 

storage/innobase/include/ut0ut.h

@@ -156,7 +156,7 @@ store the given number of bits.
 /** Determines if a number is zero or a power of two.
 @param[in]	n	number
 @return nonzero if n is zero or a power of two; zero otherwise */
-#define ut_is_2pow(n) UNIV_LIKELY(!((n) & ((n) - 1)))
+#define ut_is_2pow(n) (!((n) & ((n) - 1)))
 
 /** Functor that compares two C strings. Can be used as a comparator for
 e.g. std::map that uses char* as keys. */