www/qt6-webengine: fix build on armv7

Improve two patches with more complete variants from devel/electron19.
Patch bundled boringssl with additional patches from the same port.
Avoid an OOM condition by using the same extra patch previously only
used on i386. In that patch, decreate BROTLI_PARAM_QUALITY further
to 4 to avoid flakiness on armv7.

Obtained from: devel/electron19
Approved by: kai (with hat: kde, maintainer)
PR: 271228