patch 8.1.0779: argument for message functions is inconsistent

Problem:    Argument for message functions is inconsistent.
Solution:   Make first argument to msg() "char *".
diff --git a/src/farsi.c b/src/farsi.c
index ebed47e..48dd991 100644
--- a/src/farsi.c
+++ b/src/farsi.c
@@ -1719,7 +1719,7 @@
 
     /* Assume the screen has been messed up: clear it and redraw. */
     redraw_later(CLEAR);
-    MSG_ATTR(farsi_text_1, HL_ATTR(HLF_S));
+    msg_attr(farsi_text_1, HL_ATTR(HLF_S));
 }
 
 /*
@@ -1747,7 +1747,7 @@
 
     /* Assume the screen has been messed up: clear it and redraw. */
     redraw_later(CLEAR);
-    MSG_ATTR(farsi_text_2, HL_ATTR(HLF_S));
+    msg_attr(farsi_text_2, HL_ATTR(HLF_S));
 }
 
 /*
@@ -2150,13 +2150,13 @@
 	{
 	    p_fkmap = 0;
 	    do_cmdline_cmd((char_u *)"set norl");
-	    MSG("");
+	    msg("");
 	}
 	else
 	{
 	    p_fkmap = 1;
 	    do_cmdline_cmd((char_u *)"set rl");
-	    MSG("");
+	    msg("");
 	}
 
 	curwin->w_farsi = curwin->w_farsi ^ W_R_L;