More specific

Change-Id: I7e6490c5b50a236a5f070e98d4501e7dd5a90307
UNO_JAVA_JFW_PLUGIN is long gone

...since e7f7d511a3ad39faef431bdfc2a79fa090d0b5f7 etc. "INTEGRATION: CWS
jl15: #i37828# removed support of bootstrap parameters UNO_JAVA_JFW_DISABLE and
UNO_JAVA_JFW_PLUGIN"

Change-Id: Ia70fa9919b4b55e8b13473602cfca723f554ec30
Remove jvmfwk plugin feature

...which was effectively unused; there only ever was a single sunjavaplugin that
is now folded directly into jvmfwk.  Leaves room for further clean up.

Change-Id: I14dd2a3a09bd1ce9a8c3f5c156628ec11d954a0b