[ARM] pxa/dma: add debugfs entries
[ARM] pxa/dma: add debugfs entries

Add some debug information for PXA DMA :
 - descriptors queued
 - channels state
 - global state

--
Since V1: reverted to old register access (no more dma_readl() or dma_writel()).

Signed-off-by: Robert Jarzmik <94b2a0a74cb42a2dd0cf1b763601af7f13907aa9@free.fr>
Signed-off-by: Eric Miao <60e376623d7bcedd53f4c51cbb2c060fb40a4887@gmail.com>

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