gnu: ots: Use 'modify-phases' syntax.

* gnu/packages/ots.scm (ots)[arguments]: Use 'modify-phases' syntax.

gnu/packages/ots.scm

@@ -53,8 +53,9 @@
      ;; before libots-1.la has been built.
      '(#:parallel-build? #f
 
-       #:phases (alist-cons-after
-                 'configure 'set-shared-lib-extension
+       #:phases
+       (modify-phases %standard-phases
+         (add-after 'configure 'set-shared-lib-extension
            (lambda _
              ;; For some reason, the 'libtool' script (from Libtool
              ;; 1.5.2, Debian variant) sets 'shrext_cmds' instead of
@@ -62,8 +63,8 @@
              ;; This leads to the creation of 'libots-1' instead of
              ;; 'libots-1.so'.  Fix that.
              (substitute* "libtool"
-                     (("shrext_cmds") "shrext")))
-                 %standard-phases)))
+               (("shrext_cmds") "shrext"))
+             #t)))))
     (inputs
       `(("glib" ,glib)
         ("popt" ,popt)