fiq_debugger: use pt_regs for registers

fiq_debugger: use pt_regs for registers

IRQ mode already passes in a struct pt_regs from get_irq_regs().
FIQ mode passes in something similar but not identical to a
struct pt_regs - FIQ mode stores the spsr of the interrupted mode
in slot 17, while pt_regs expects orig_r0.

Replace the existing mixture of void *regs, unsigned *regs, and
struct pt_regs * const with const struct pt_regs *.  Modify
dump_regs not to print the spsr since it won't be there in a
struct pt_regs anyways.  Modify dump_allregs to highlight the
mode that was interrupted, making spsr easy to find there.

Change-Id: Ibfe1723d702306c7605fd071737d7be9ee9d8c12
Signed-off-by: Colin Cross <ccross@android.com>