bcm-2xxx-rpi: Fix select + depend CONFIG_PM Kconfig error

There is a Kconfig logic conflict as of 6ae22abe ("Merge branch
'v5.15/standard/base' into v5.15/standard/bcm-2xxx-rpi") between r-pi
SDK content:

  commit b3d4b7b5
  Author: Maxime Ripard <maxime@cerno.tech>
  Date:   Thu Aug 19 15:53:03 2021 +0200

    drm/vc4: select PM

    commit  39cf7db9b384a651d481d0b04d9dee540624302a from
    https://github.com/raspberrypi/linux.git rpi-5.15.y

and the v5.15 backport of the upstream variant of the similar commit:

  commit 80d46e73
  Author: Maxime Ripard <maxime@cerno.tech>
  Date:   Wed Jun 29 14:34:36 2022 +0200

    drm/vc4: hdmi: Depends on CONFIG_PM

    commit 72e2329e

 upstream.

If you have both "depends" and "select" for the same variable, you get:

 kernel/power/Kconfig:164:error: recursive dependency detected!
 kernel/power/Kconfig:164:       symbol PM is selected by DRM_VC4
 drivers/gpu/drm/vc4/Kconfig:2:  symbol DRM_VC4 depends on PM
 For a resolution refer to Documentation/kbuild/kconfig-language.rst
 subsection "Kconfig recursive dependency limitations"

Delete the select from the SDK and keep the mainline backport depend.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>