Drop references to $haikuVersion.

* Referring the current haiku version explicitly is not needed, since
  the RequiresUpdater takes care of setting the version of Haiku used
  for building a package.

games-arcade/slime_volley/slime_volley-2.4.2.recipe

@@ -20,7 +20,7 @@ PROVIDES="
 "
 
 REQUIRES="
-	haiku >= $haikuVersion
+	haiku
 	lib:libintl
 	lib:libsdl
 	lib:libsdl_image
@@ -36,7 +36,7 @@ BUILD_REQUIRES="
 "
 
 BUILD_PREREQUIRES="
-	haiku_devel >= $haikuVersion
+	haiku_devel
 	cmd:cmake
 	cmd:gcc
 	cmd:make