msm: camera: Query only AHB clks from dt in ISPIF

All clocks used by ISPIF are now added to DTSI.
Previously the code assumes only AHB clock is in DTSI.
Now the code is updated to query only the AHB clocks
out of all the clocks listed.

Change-Id: I7843e4eab2f0d14341a1ccb2978a84a23ed12f4d
Signed-off-by: Senthil <skrajago@codeaurora.org>