Blackfin arch: Update some inline assembly, tweak some register constraints

Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/include/asm/bfrom.h b/arch/blackfin/include/asm/bfrom.h
index cfe8024..9e4be5e 100644
--- a/arch/blackfin/include/asm/bfrom.h
+++ b/arch/blackfin/include/asm/bfrom.h
@@ -43,6 +43,11 @@
 static inline void bfrom_SoftReset(void *new_stack)
 {
 	while (1)
+		/*
+		 * We don't declare the SP as clobbered on purpose, since
+		 * it confuses the heck out of the compiler, and this function
+		 * never returns
+		 */
 		__asm__ __volatile__(
 			"sp = %[stack];"
 			"jump (%[bfrom_syscontrol]);"