soc: qcom: glink_ssr: Fix format specifier to be arch-independent

Some error messages in the glink_ssr driver use the %zu format specifier
to handle the result of the PTR_ERR macro. This causes compilation failures
on 32-bit targets.

Cast the result of PTR_ERR to an int and use the %d format specifier
instead to fix the error.

Change-Id: I9d4effefc50e83d4f3abefd49a30e5df44df1ef9
Signed-off-by: Steven Cahail <scahail@codeaurora.org>