Backport commit b884ff3 from Emacs master branch

Spelling fix for 'hfy-optimizations'
b884ff380dc341ca8dc8fcfe4357110e191216ce
Paul Eggert
Sun Apr 5 23:43:22 2015 -0700

lisp/ox-odt.el

@@ -262,7 +262,8 @@ This style is much the same as that of \"OrgFixedWidthBlock\"
 except that the foreground and background colors are set
 according to the default face identified by the `htmlfontify'.")
 
-(defvar hfy-optimisations)
+(defvar hfy-optimizations)
+(define-obsolete-variable-alias 'hfy-optimisations 'hfy-optimizations "25.1")
 (defvar org-odt-embedded-formulas-count 0)
 (defvar org-odt-embedded-images-count 0)
 (defvar org-odt-image-size-probe-method
@@ -3116,8 +3117,8 @@ and prefix with \"OrgSrc\".  For example,
 			       (" " "<text:s/>")
 			       ("	" "<text:tab/>")))
 	 (hfy-face-to-css 'org-odt-hfy-face-to-css)
-	 (hfy-optimisations-1 (copy-sequence hfy-optimisations))
-	 (hfy-optimisations (add-to-list 'hfy-optimisations-1
+	 (hfy-optimizations-1 (copy-sequence hfy-optimizations))
+	 (hfy-optimizations (add-to-list 'hfy-optimizations-1
 					 'body-text-only))
 	 (hfy-begin-span-handler
 	  (lambda (style text-block text-id text-begins-block-p)