disp: msm: dsi: fix boot display name parsing

The boot_disp_en flag for secondary display is getting enabled
all the time, even if its boot_param string is empty.
Correct the boot display name parsing from boot_param string
to fix this issue.

Change-Id: Ica1465611f592b22518061987571919838914891
Signed-off-by: Rajeev Nandan <[email protected]>

msm/dsi/dsi_display.c

@@ -2616,7 +2616,7 @@ static int dsi_display_parse_boot_display_selection(void)
 		strlcpy(disp_buf, boot_displays[i].boot_param,
 			MAX_CMDLINE_PARAM_LEN);
 
-		pos = strnstr(disp_buf, ":", MAX_CMDLINE_PARAM_LEN);
+		pos = strnstr(disp_buf, ":", strlen(disp_buf));
 
 		/* Use ':' as a delimiter to retrieve the display name */
 		if (!pos) {