hw/char: Move two more files from specific_ss to softmmu_ss

The code for these two devices seems to be independent from any
target specific macros. "riscv_htif.c" is used for both, riscv32 and
riscv64, so by moving this to the common code source set, we can
avoid to compile it twice every time.
"goldfish_tty.c" is only used for one target at the moment, but
since it is a paravirtualized device, it could get useful for other
targets one day, so let's move it now, too.

Message-Id: <20230411173206.1511621-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
1 file changed