ASoC: max98090: remove duplicate status reads and useless assignmment

The logic for the jack detection has not changed since the first
commit for this driver. Remove a duplicate read and remove useless
assignment

sound/soc/codecs/max98090.c:2170:6: style: Variable 'reg' is
reassigned a value before the old one has been
used. [redundantAssignment]
 reg = snd_soc_component_read(component, M98090_REG_JACK_STATUS);
     ^

sound/soc/codecs/max98090.c:2161:7: note: reg is assigned
  reg = snd_soc_component_read(component, M98090_REG_JACK_STATUS);
      ^

sound/soc/codecs/max98090.c:2170:6: note: reg is overwritten
 reg = snd_soc_component_read(component, M98090_REG_JACK_STATUS);
     ^

sound/soc/codecs/max98090.c:2170:6: style: Variable 'reg' is
reassigned a value before the old one has been
used. [redundantAssignment]
 reg = snd_soc_component_read(component, M98090_REG_JACK_STATUS);
     ^

sound/soc/codecs/max98090.c:2167:7: note: reg is assigned
  reg = snd_soc_component_read(component, M98090_REG_JACK_STATUS);
      ^

sound/soc/codecs/max98090.c:2170:6: note: reg is overwritten
 reg = snd_soc_component_read(component, M98090_REG_JACK_STATUS);
     ^

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210804192456.278702-2-pierre-louis.bossart@linux.intel.com


Signed-off-by: Mark Brown <broonie@kernel.org>