shm: Don't try to put a whole bunch of clipped XY image contents.

sw and sh are smaller than w and h, and our temporary pixmap is only
sw by sh, and we copy out an area of sw by sh.  There's no need to go
asking the driver to putimage w by h, and glamor acceleration tripped
over this by making a temporary of the fbPutImage results of size w by
h, without running it through the clip first.
4 jobs for shmputimage-fix in 6 minutes and 15 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Docker Image
passed #2179776
debian-testing

00:00:30

 
  Build And Test
passed #2179777
autotools

00:05:45

passed #2179778
meson

00:02:28

passed #2179779
meson-noglamor

00:01:53