Fix typo

Change-Id: I3bdc875963c413996ffb6403c44968447dbb3131
Reviewed-on: https://gerrit.libreoffice.org/42629Reviewed-by: Tamás Zolnai <tamas.zolnai@collabora.com>
Tested-by: Tamás Zolnai <tamas.zolnai@collabora.com>

writerperfect/source/writer/EPUBExportFilter.cxx

@@ -30,7 +30,7 @@ namespace libepubgen
 {
     enum EPUBStylesMethod
     {
-        EPUB_STYLES_METHOD_CSS, //< The styles will be described in a seprarate CSS file.
+        EPUB_STYLES_METHOD_CSS, //< The styles will be described in a separate CSS file.
         EPUB_STYLES_METHOD_INLINE, //< The styles will be described inline.
     };
 }