powerpc/ps3: spu.c: fix enum and Return kernel-doc warnings

powerpc/ps3: spu.c: fix enum and Return kernel-doc warnings

Fix enum and function return value kernel-doc warnings:

Warning: spu.c:36 Excess enum value '%spe_type_logical' description in 'spe_type'
Warning: spu.c:78 Excess enum value '%spe_ex_state_unexecutable' description in 'spe_ex_state'
Warning: spu.c:78 Excess enum value '%spe_ex_state_executable' description in 'spe_ex_state'
Warning: spu.c:78 Excess enum value '%spe_ex_state_executed' description in 'spe_ex_state'
Warning: spu.c:190 No description found for return value of 'setup_areas'

Fixes: de91a5342995 ("[POWERPC] ps3: add spu support")
Fixes: b47027795a22 ("powerpc/ps3: Fix ioremap of spu shadow regs")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260225055328.249204-1-rdunlap@infradead.org