r300: fix offsets for clipping and scissors

12 jobs for r300/clipping in 1 minute and 32 seconds (queued for 26 seconds)
latest
Status Name Job ID Coverage
  Docker Image
passed container-build #16077236

00:00:26

 
  Build
passed build-clang: [1.18] #16077243

00:00:51

passed build-clang: [1.19] #16077244

00:00:45

passed build-clang: [1.20] #16077242

00:00:46

passed build-distcheck #16077237

00:01:06

passed build-gcc: [1.16] #16077238

00:00:51

passed build-gcc: [1.17] #16077239

00:00:50

passed build-gcc: [1.18] #16077240

00:00:43

passed build-gcc: [1.19] #16077241

00:00:49

passed build-noglamor: [1.13] #16077245

00:00:49

passed build-noglamor: [1.14] #16077246

00:00:42

passed build-noglamor: [1.15] #16077247

00:00:49