prism54: remove questionable down_interruptible usage

Reviewing the semaphore usage I noticed these down_interruptible calls.  Most
of these aren't returning anything, so a caller can't tell if the operation
completed or not.  prism54_wpa_bss_ie_get() returns zero, but it's treated as
the function failing which doesn't seem correct.
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/prism54/isl_ioctl.c

@@ -165,8 +165,7 @@ prism54_update_stats(struct work_struct *work)
 	struct obj_bss bss, *bss2;
 	union oid_res_t r;
 
-	if (down_interruptible(&priv->stats_sem))
-		return;
+	down(&priv->stats_sem);
 
 /* Noise floor.
  * I'm not sure if the unit is dBm.
@@ -1793,8 +1792,7 @@ prism54_clear_mac(struct islpci_acl *acl)
 	struct list_head *ptr, *next;
 	struct mac_entry *entry;
 
-	if (down_interruptible(&acl->sem))
-		return;
+	down(&acl->sem);
 
 	if (acl->size == 0) {
 		up(&acl->sem);
@@ -2116,8 +2114,7 @@ prism54_wpa_bss_ie_add(islpci_private *priv, u8 *bssid,
 	if (wpa_ie_len > MAX_WPA_IE_LEN)
 		wpa_ie_len = MAX_WPA_IE_LEN;
 
-	if (down_interruptible(&priv->wpa_sem))
-		return;
+	down(&priv->wpa_sem);
 
 	/* try to use existing entry */
 	list_for_each(ptr, &priv->bss_wpa_list) {
@@ -2178,8 +2175,7 @@ prism54_wpa_bss_ie_get(islpci_private *priv, u8 *bssid, u8 *wpa_ie)
 	struct islpci_bss_wpa_ie *bss = NULL;
 	size_t len = 0;
 
-	if (down_interruptible(&priv->wpa_sem))
-		return 0;
+	down(&priv->wpa_sem);
 
 	list_for_each(ptr, &priv->bss_wpa_list) {
 		bss = list_entry(ptr, struct islpci_bss_wpa_ie, list);