um: segv: Save regs only in case of a kernel mode fault
um: segv: Save regs only in case of a kernel mode fault

...otherwise me lose user mode regs and the resulting
stack trace is useless.

Signed-off-by: Richard Weinberger <320bca71fc381a4a025636043ca86e734e31cf8b@nod.at>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs