remoteproc: print hex numbers with a leading 0x format

There are couple of debug statements that are printing hexadecimal
numbers without the leading 0x. Fix these and use the standard 0x%x
format specifier so that there is no confusion when looking at the
traces.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>