Fix some typos (harmless) (#14079)

frontend/document/koptinterface.lua

@@ -297,7 +297,7 @@ function KoptInterface:reflowPage(doc, pageno, bbox, background)
         kc:setPreCache()
         self.bg_thread = true
     end
-    -- Caculate zoom.
+    -- Calculate zoom.
     kc.zoom = (1.5 * kc.zoom * kc.quality * kc.dev_width) / bbox.x1
     -- Generate pixmap.
     local page = doc._document:openPage(pageno)
@@ -1433,7 +1433,7 @@ end
 local function get_pattern_list(pattern, case_insensitive)
     -- pattern list of single words
     local plist = {}
-    -- (as in util.splitToWords(), but only splitting on spaces, keeping punctuations)
+    -- (as in util.splitToWords(), but only splitting on spaces, keeping punctuation marks)
     for word in util.gsplit(pattern, "%s+") do
         if util.hasCJKChar(word) then
             for char in util.gsplit(word, "[\192-\255][\128-\191]+", true) do