s5k3l6xx: Don't touch integration time in frame regs

Otherwise it gets reset behind v4l2's back when starting streaming.
2 jobs for integration-time in 67 minutes and 51 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #347355
librem5
build:aarch64

00:44:07

passed #347356
librem5:arm64
build:deb

01:07:51