dmaengine/dw_dmac: Don't use magic number for total number of channels
dmaengine/dw_dmac: Don't use magic number for total number of channels

Total number of channels is passed in pdata->nr_channels variable, thus we must
not use magic number '7' for total number of channels.

Signed-off-by: Viresh Kumar <5ff32272b3d9f86512eddc8e0af523fc6f7924e5@st.com>
Signed-off-by: Vinod Koul <5cf69c63beb17bf38d63aa0e923ee8256af0e205@linux.intel.com>

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,KristFoundation/Programs