Threaded input doesn't use SIGIO anymore, but existing drivers using
xf86BlockSIGIO and xf86ReleaseSIGIO probably want to lock the input
mutex during those operations. Provide inline functions to do this
which are marked as 'deprecated' so that drivers will get warnings
until they are changed.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>