Log Message:
devel/php-xdebug: update to 2.9.4

Update php-xdebug to 2.9.4.

Mon, Mar 23, 2020 - xdebug 2.9.4

= Fixed bugs:

- Fixed issue #1763: Crash while setting opcode overrides in ZTS mode.
- Fixed issue #1766: Using the DBGp detach command disables remote debugging for \ 
the whole process.