MAINTAINERS: Update maintainers for pmc_core driver

Update MAINTAINERS file for pmc_core driver to reflect the current
maintainers.

Cc: Vishwanath Somayaji <vishwanath.somayaji@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@intel.com>
Cc: David E. Box <david.e.box@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Acked-by: Vishwanath Somayaji <vishwanath.somayaji@intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Rajneesh Bhardwaj <irenic.rajneesh@gmail.com>
Link: https://lore.kernel.org/r/20201007035108.31078-5-david.e.box@linux.intel.com


Signed-off-by: Hans de Goede <hdegoede@redhat.com>