Allow PHP 7 to install in Apache 2 on OS X

This fixes the fundamental part of #67910.  The complete change from
php5 -> php7 in sapi/* still needs to be done.
Remove 550+ compile warnings on OS X

The warnings had the signature:
php-src/ext/mysqlnd/mysqlnd_debug.h:127:25: note: expanded from macro 'DBG_ENTER_EX2'
                          if (dbg_skip_trace); /* shut compiler's mouth */\
                                             ^
php-src/ext/mysqlnd/mysqlnd.c:114:2: note: put the semicolon on a separate line to silence this warning
Merge branch 'PHP-5.5' into PHP-5.6

* PHP-5.5:
  Remove 550+ compile warnings on OS X
Merge branch 'PHP-5.6'

* PHP-5.6:
  Remove 550+ compile warnings on OS X