Staging: remove drivers/char/scc.h as it should have gone a while ago

This was needed by one of the generic serial drivers that was removed a
while ago.  No one even noticed that the driver could not be built
properly while it was in the staging directory.

So this removed the unneeded .h file.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>