msm: pil: Print error messages when pil_force_{boot,shutdown} fails

If a peripheral is not registered and a driver calls
pil_force_{boot,shutdown}() the function silently returns an
error value or void. Print an error message so that log analysis
can find these problems more easily.

Change-Id: I6b535c2e7ac548b502941f37306f61890ef9b569
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>