meta-agl-bsp: Fix rc.pvr.service dependency for meta-rcar-gen3

meta-agl-bsp: Fix rc.pvr.service dependency for meta-rcar-gen3

Undo the out of date tweak of rc.pvr.service to make it a dependency
of weston@.service done in meta-rcar-gen3's gles-user-module recipe.
For now, just tweak the dependency back to weston.service in our
bbappend in meta-agl-bsp, this can be removed when meta-rcar-gen3
includes a fix.

Bug-AGL: SPEC-4607

Change-Id: I16ef13d2af9b2ed485ce8b98501f39bf96aba3e2
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/28142
Tested-by: Jenkins Job builder account
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>