drivers: iommu, leds, input, clk, devfreq: fix warnings.

Fix some variable initializations which would otherwise cause
forbidden warnings.

Change-Id: I4066ebf3cb18bf5e2749a44edb137458b7c525d8
Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Signed-off-by: David Keitel <dkeitel@codeaurora.org>
Signed-off-by: Narendra Muppalla <narendram@codeaurora.org>