Update all versions to build in immediate source directory.

The build-php directory was only there for building multiple packages.
With only one package, that directory is not needed.
Remove "php" comment that doesn't help.

The php comment was there from the original PKGBUILD to differentiate
the php build from that of the other packages being built.  The comment
is just useless now. :)
Remove Contributor comment.
Fix indentation (tabs -> spaces).
Remove empty makedepends.
Inline the configure options.

These configuration options are easier to follow inline than as a
separate string variable.