[patch] genirq: update comments related to buslock support

[Frank Rowand <frank.rowand@am.sony.com>]

Update comments to match code change in 70aedd24

Signed-off-by: Frank Rowand <frank.rowand@am.sony.com>

---
 kernel/irq/manage.c |    7 	5 +	2 -	0 !
 1 file changed, 5 insertions(+), 2 deletions(-)

Index: b/kernel/irq/manage.c
===================================================================
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -236,7 +236,8 @@ void __disable_irq(struct irq_desc *desc
  *	Unlike disable_irq(), this function does not ensure existing
  *	instances of the IRQ handler have completed before returning.
  *
- *	This function may be called from IRQ context.
+ *	This function may be called from IRQ context only when
+ *	desc->chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
  */
 void disable_irq_nosync(unsigned int irq)
 {
@@ -264,7 +265,9 @@ EXPORT_SYMBOL(disable_irq_nosync);
  *	to complete before returning. If you use this function while
  *	holding a resource the IRQ handler may need you will deadlock.
  *
- *	This function may be called - with care - from IRQ context.
+ *	This function may be called - with care - from IRQ context only when
+ *	desc->chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
+ *	See synchronize_irq() comments for explanation of "with care".
  */
 void disable_irq(unsigned int irq)
 {