Blackfin arch:  merge adeos blackfin part to arch/blackfin/

[Mike Frysinger <vapier.adi@gmail.com>:
 - handle bf531/bf532/bf534/bf536 variants in ipipe.h
 - cleanup IPIPE logic for bfin_set_irq_handler()
 - cleanup ipipe asm code a bit and add missing ENDPROC()
 - simplify IPIPE code in trap_c
 - unify some of the IPIPE code and fix style
 - simplify DO_IRQ_L1 handling with ipipe code
 - revert IRQ_SW_INT# addition from ipipe merge
 - remove duplicate get_{c,s}clk() prototypes
]

Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/kernel/entry.S b/arch/blackfin/kernel/entry.S
index c0c3fe8..a9cfba9 100644
--- a/arch/blackfin/kernel/entry.S
+++ b/arch/blackfin/kernel/entry.S
@@ -42,6 +42,10 @@
 #endif
 
 ENTRY(_ret_from_fork)
+#ifdef CONFIG_IPIPE
+	[--sp] = reti; 		/* IRQs on. */
+	SP += 4;
+#endif /* CONFIG_IPIPE */
 	SP += -12;
 	call _schedule_tail;
 	SP += 12;