ARM: CSR: fix build error due to new mdesc->dma_zone_size
ARM: CSR: fix build error due to new mdesc->dma_zone_size

commit 98b0124f0e2b88
"ARM: mach-prima2: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size"
causes building error:
arch/arm/mach-prima2/prima2.c:39:19: error: 'SZ_256M' undeclared here
(not in a function)

Signed-off-by: Barry Song <3786fe3782c2aabdbf77b421a4257e7e0a1dbb38@csr.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs