add --not-as-needed linker option on unxgcc platform
add --not-as-needed linker option on unxgcc platform

Signed-off-by: Stephan Bergmann <sbergman@redhat.com>:  Ubuntu changed ld to
assume --as-needed by default, but there are places in LO that implicitly depend
on --no-as-needed, like test_smoketest lib that is an empty wrapper around
smoketest lib, or UNO executables having to link against all URE published libs
so that LO extensions are guaranteed to find the URE libs.

Change-Id: I88fc79766ffb4a4ca8ead05bb9033c686120cf2c

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core