ASoC: rt1015p: remove dependency on GPIOLIB

ASoC: rt1015p: remove dependency on GPIOLIB

commit aade78eea634e ("ASoC: Fix gpiolib dependencies") removed a
series of unnecessary dependencies on GPIOLIB when the gpio was
optional.

A similar simplification seems valid for rt1015p, so remove the
dependency as well. This will avoid the following warning

  WARNING: unmet direct dependencies detected for SND_SOC_RT1015P

     Depends on [n]: SOUND [=y] && !UML && SND [=y] && SND_SOC [=y] &&
     GPIOLIB [=n]

     Selected by [y]:

     - SND_SOC_INTEL_SOF_RT5682_MACH [=y] && SOUND [=y] && !UML && SND
       [=y] && SND_SOC [=y] && SND_SOC_INTEL_MACH [=y] &&
       (SND_SOC_SOF_HDA_LINK [=y] || SND_SOC_SOF_BAYTRAIL [=n]) && I2C
       [=y] && ACPI [=y] && (SND_HDA_CODEC_HDMI [=y] &&
       SND_SOC_SOF_HDA_AUDIO_CODEC [=y] && (MFD_INTEL_LPSS [=y] ||
       COMPILE_TEST [=y]) || SND_SOC_SOF_BAYTRAIL [=n] &&
       (X86_INTEL_LPSS [=n] || COMPILE_TEST [=y]))

Reported-by: kernel test robot <yujie.liu@intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20220517172647.468244-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>