www/onlyoffice-documentserver: partial armv7 fix

This makes the build not stop immediately due to a wrong target.
Now the build fails in src/codegen/arm/cpu-arm.cc due to v8 using
Linux' arm_sync_icache which we don't have. I think I have patched
that one before...

Approved by: portmgr (build fix blanket)
MFH: 2025Q3

(cherry picked from commit af8fdbae92d5111154b8346f8e278d54cc8d52b2)