patch 9.1.0747: various typos in repo found

Problem:  various typos in repo found
Solution: Fix typos (zeertzjq)

closes: #15749

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/option.c

@@ -186,7 +186,7 @@ set_init_default_backupskip(void)
 	    item = alloc(itemsize);
 	    if (item != NULL)
 	    {
-		// add a preceeding comma as a separator after the first item
+		// add a preceding comma as a separator after the first item
 		size_t	itemseplen = (ga.ga_len == 0) ? 0 : 1;
 		size_t	itemlen;
 

src/testdir/commondumps.vim

@@ -23,7 +23,7 @@ enddef
 
 # Search for the "failed" directory in the passed _subtreedirname_ directories
 # (usually "\<src\>" or "\<syntax\>") and, if found, select its passed _count_
-# occurence, add all its "*.dump" files to the argument list and list them;
+# occurrence, add all its "*.dump" files to the argument list and list them;
 # also define a BufRead autocommand that would invoke "Render()" for every
 # "*.dump" file.
 def g:Init(subtreedirname: string, count: number)

src/testdir/test_listdict.vim

@@ -1621,7 +1621,7 @@ endfunc
 
 " Test for using id()
 def Test_id_with_dict()
-  # demonstate a way that "id(item)" differs from "string(item)"
+  # demonstrate a way that "id(item)" differs from "string(item)"
   var d1 = {one: 1}
   var d2 = {one: 1}
   var d3 = {one: 1}

src/testdir/test_normal.vim

@@ -4274,7 +4274,7 @@ func Test_halfpage_longline()
 endfunc
 
 " Test for Ctrl-E with long line and very narrow window,
-" used to cause an inifite loop
+" used to cause an infinite loop
 func Test_scroll_longline_no_loop()
   4vnew
   setl smoothscroll number showbreak=> scrolloff=2

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    747,
 /**/
     746,
 /**/

src/window.c

@@ -4609,7 +4609,7 @@ free_tabpage(tabpage_T *tp)
  * Otherwise put it just before tab page "after".
  *
  * Does not trigger WinNewPre, since the window structures
- * are not completly setup yet and could cause dereferencing
+ * are not completely setup yet and could cause dereferencing
  * NULL pointers
  *
  * Return FAIL or OK.