serial: ucc_uart: Fix multiple address space type errors

serial: ucc_uart: Fix multiple address space type errors

sparse reports multiple problems with address space type.

Most problems are linked to missing __iomem qualifier.

Others are caused by dereferencing __iomem addresses.

Fix all this by adding missing __iomem and using ioread32be().

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312050412.zN2PKArS-lkp@intel.com/
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Link: https://lore.kernel.org/r/e49deeb079391ff7273ec32f5563df94cf70bc95.1701781976.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>