Fix hard freeze in pic_handle_intr() for PPC_IBM403.

Not clearly documented in reference manual, but DCR_EXISR register is
not updated immediately after some bits are cleared by mtdcr, no matter
whe

Fix hard freeze in pic_handle_intr() for PPC_IBM403.

Not clearly documented in reference manual, but DCR_EXISR register is
not updated immediately after some bits are cleared by mtdcr, no matter
whether sync (= eieio) and/or isync are issued.

Therefore, we have to manage our own status mask in the interrupt handler.
This is what we did in obsoleted powerpc/ibm4xx/intr.c.

With this change, my Explora 451 works just fine with serial console!
Fix for framebuffer console will be committed soon.

show more ...

Switch to intr_establish_xname().

Include missing opt_ppcarch.h and opt_uic.h.

Style and cosmetic changes. No binary changes intended.

Remove unused macros.

Fix IPL for cascading pic to HIGH.

Use kmem instead of malloc. Remove unneeded <sys/malloc.h> includes.

Fix the mistake in level and type.

Change IBM4xx to use the common powerpc PIC framework.
Consolidate most ibm4xx initppc function into ibm4xx_init
and Make all IBM4xx use it.
Change explora to use initppc instead of bootstrap.