MAINTAINERS: Add myself as VFIO-platform reviewer

MAINTAINERS: Add myself as VFIO-platform reviewer

While my work at Google Cloud focuses on various areas of the kernel,
my background in IOMMU and the VFIO subsystem motivates me to help with
the maintenance effort for vfio-platform (based on the discussion [1])
and ensure its continued health.

Link: https://lore.kernel.org/all/aKxpyyKvYcd84Ayi@google.com/
Signed-off-by: Pranjal Shrivastava <praan@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20250901191619.183116-1-praan@google.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>