disp: msm: dp: return -ENODEV when USBPD module is not enabled

Return ERR_PTR with -ENODEV when the USBPD module is not
enabled. This allows the DP driver to handle the failure
correctly and prevents any potential NULL pointer
dereferencing in the clean up path.

Change-Id: I4fbc559276bebe770a27935243a59c10c1bb5491
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>

msm/dp/dp_usbpd.h

@@ -65,7 +65,7 @@ void dp_usbpd_put(struct dp_hpd *pd);
 static inline struct dp_hpd *dp_usbpd_get(struct device *dev,
 		struct dp_hpd_cb *cb)
 {
-	return NULL;
+	return ERR_PTR(-ENODEV);
 }
 
 static inline void dp_usbpd_put(struct dp_hpd *pd)