KVM: MIPS: Drop pr_debug from memslot commit to avoid using "mem"

Remove an old (circa 2012) kvm_debug from kvm_arch_commit_memory_region()
to print basic information when committing a memslot change.  The primary
motivation for removing the kvm_debug is to avoid using @mem, the user
memory region, so that said param can be removed.

Alternatively, the debug message could be converted to use @new, but that
would require synthesizing select state to play nice with the DELETED
case, which will pass NULL for @new in the future.  And there's no
argument to be had for dumping generic information in an arch callback,
i.e. if there's a good reason for the debug message, then it belongs in
common KVM code where all architectures can benefit.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <446929a668f6e1346751571b71db41e94e976cdf.1638817639.git.maciej.szmigiero@oracle.com>