patch 8.1.2243: typos in comments

Problem:    Typos in comments.
Solution:   Fix the typos. (Dominique Pelle, closes #5160)  Also adjust
            formatting a bit.
diff --git a/src/insexpand.c b/src/insexpand.c
index 31b952b..e42819a 100644
--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -1612,7 +1612,7 @@
 #ifdef FEAT_SPELL
 	spell_bad_len = 0;	// need to redetect bad word
 #endif
-	// Matches were cleared, need to search for them now.  Befor drawing
+	// Matches were cleared, need to search for them now.  Before drawing
 	// the popup menu display the changed text before the cursor.  Set
 	// "compl_restarting" to avoid that the first match is inserted.
 	pum_call_update_screen();
@@ -2858,7 +2858,7 @@
 
 	    //	Buffers other than curbuf are scanned from the beginning or the
 	    //	end but never from the middle, thus setting nowrapscan in this
-	    //	buffers is a good idea, on the other hand, we always set
+	    //	buffer is a good idea, on the other hand, we always set
 	    //	wrapscan for curbuf to avoid missing matches -- Acevedo,Webb
 	    save_p_ws = p_ws;
 	    if (ins_buf != curbuf)