powerpc/srio: Fix the compile errors when building with 64bit

For the file "arch/powerpc/sysdev/fsl_rmu.c", there will be some compile
errors while using the corenet64_smp_defconfig:

.../fsl_rmu.c:315: error: cast from pointer to integer of different size
.../fsl_rmu.c:320: error: cast to pointer from integer of different size
.../fsl_rmu.c:320: error: cast to pointer from integer of different size
.../fsl_rmu.c:320: error: cast to pointer from integer of different size
.../fsl_rmu.c:330: error: cast to pointer from integer of different size
.../fsl_rmu.c:332: error: cast to pointer from integer of different size
.../fsl_rmu.c:339: error: cast to pointer from integer of different size
.../fsl_rmu.c:340: error: cast to pointer from integer of different size
.../fsl_rmu.c:341: error: cast to pointer from integer of different size
.../fsl_rmu.c:348: error: cast to pointer from integer of different size
.../fsl_rmu.c:348: error: cast to pointer from integer of different size
.../fsl_rmu.c:348: error: cast to pointer from integer of different size
.../fsl_rmu.c:659: error: cast from pointer to integer of different size
.../fsl_rmu.c:659: error: format '%8.8x' expects type 'unsigned int',
                   but argument 5 has type 'size_t'
.../fsl_rmu.c:985: error: cast from pointer to integer of different size
.../fsl_rmu.c:997: error: cast to pointer from integer of different size

Rewrote the corresponding code with the support of 64bit building.

Signed-off-by: Liu Gang <Gang.Liu@freescale.com>
Signed-off-by: Shaohui Xie <Shaohui.Xie@freescale.com>
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>