[PHP]Added missing files and fix phpext_protobuf_ptr export in pecl version

[Cotch22]

in order to compile php with protobuf from pecl.

now the pecl version of protobuf does not contain output to phpext_protobuf_ptr, causing me to manually add this code

extern zend_module_entry protobuf_module_entry;
#define phpext_protobuf_ptr &protobuf_module_entry

every time I rebuild PHP with --enable-protobuf

Please Add this file to PECL version.
https://pecl.php.net/package/protobuf

Thank!

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[deannagarcia]

Thanks for this fix! If you sign the CLA I can get it merged for you.

[Cotch22]

Thanks for this fix! If you sign the CLA I can get it merged for you.

Thanks. I have already signed.