powerpc/8xx: Shorten irq_chip name for the SIU
show_interrupts() expects the irq_chip name to be max 8 characters
otherwise everything get misaligned
# cat /proc/interrupts
CPU0
17: 0 CPM PIC 0 Level error
19: 0 MPC8XX SIU 15 Level tbint
20: 90 CPM PIC 4 Level cpm_uart
38: 29746 MPC8XX SIU 5 Level fs_enet-mac
39: 0 MPC8XX SIU 7 Level fs_enet-mac
47: 401 CPM PIC 5 Level fsl_spi
68: 1 MPC8XX SIU 2 Level phy_interrupt, phy_interrupt, phy_interrupt
LOC:
7225485 Local timer interrupts for timer event device
LOC: 9 Local timer interrupts for others
SPU: 0 Spurious interrupts
PMI: 0 Performance monitoring interrupts
MCE: 0 Machine check exceptions
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>