Replace obsolete AC_STRUCT_ST_BLKSIZE and AC_STRUCT_ST_RDEV

Replace obsolete AC_STRUCT_ST_BLKSIZE and AC_STRUCT_ST_RDEV

Autoconf 2.50 released in 2001 has made several macros obsolete. Instead
of the AC_STRUCT_ST_BLKSIZE and AC_STRUCT_ST_RDEV the new
AC_CHECK_MEMBERS should be used.

When checking for the presence of stat struct members st_blkzize and
st_rdev the new AC_CHECK_MEMBERS macro defines new constants
HAVE_STRUCT_STAT_ST_BLKSIZE and HAVE_STRUCT_STAT_ST_RDEV.

Old constants HAVE_ST_BLKSIZE and HAVE_ST_RDEV need to be replaced
respectively in PHP code (this patch) and in PHP extenstions if they use
them.

PHP 5.4 to 7.1 require Autoconf 2.59+ version, PHP 7.2 and above require
2.64+ version, and the PHP 7.2 phpize script requires 2.59+ version which
are all greater than above mentioned 2.50 version.