octeontx2: Annotate mmio regions as __iomem

This patch removes unnecessary typecasts by marking the
mbox_regions array as __iomem since it is used to store
pointers to memory-mapped I/O (MMIO) regions. Also simplified
the call to readq() in PF driver by removing redundant type casts.

Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Link: https://patch.msgid.link/1749484309-3434-1-git-send-email-sbhatta@marvell.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>