patch 7.4.822
Problem:    More problems reported by coverity.
Solution:   Avoid the warnings. (Christian Brabandt)
diff --git a/src/os_unix.c b/src/os_unix.c
index f53faa3..2439c5e 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -7001,7 +7001,7 @@
 	/* Rely on the same mouse code for the duration of this */
 	mouse_code = find_termcode(mouse_name);
 	prev_row = mouse_row;
-	prev_row = mouse_col;
+	prev_col = mouse_col;
 	xterm_trace = 2;
 
 	/* Find the offset of the chars, there might be a scrollbar on the