make php to multi package

[Takahiro Kambe <taca%back-street.net@localhost>]

Hi,

Currently, lang/php{56,74,80,81} packages cannot be installed at the
same time.  It was reasonable when using PHP as apache http server's
loadble module (ap-php).

But using php-fpm, multiple version of PHP could be usable at the same
time.

I modified lang/php's frameworks to make php as multi-packages.

	lang/php56	=>	php56-5.6.40
	lang/php74	=>	php74-7.4.33
	lang/php80	=>	php80-8.0.25
	lang/php81	=>	php81-8.1.12

I've worked in my private pkgsrc tree and most of packages are now
built successfully.  Here is current diff against pkgsrc head.

ftp://ftp.back-street.net/pub/netbsd/pkgsrc/pkgsrc-php-2022110000.diff.xz

To do:

1. I don't run real web server yet, so require run time test.
2. Make more clean up to lang/php frameworks.

Any comment?

-- 
Takahiro Kambe <taca%back-street.net@localhost>