Revert "build.xml: allow env.FLEX_HOME"

This reverts commit 57f105dee510965325971edcce80486b92899247.

build.xml

diff --git a/build.xml b/build.xml
index c0e4ccf..4fffecb 100644
--- a/build.xml
+++ b/build.xml
@@ -24,12 +24,7 @@
          Override on cmd line with -D=FLEX_HOME=path. -->
 	<property file="${basedir}/local.properties"/>
     <!-- Default Flex SDK is the trunk.  Override on cmd line with -D=FLEX_HOME=path. -->
-	<condition property="FLEX_HOME" value="${env.FLEX_HOME}">
-		<available file="${env.FLEX_HOME}/lib/compc.jar" type="file" />
-	</condition>
-	<condition property="FLEX_HOME" value="${basedir}/../flex-sdk">
-		<available file="${basedir}/../flex-sdk/lib/compc.jar" type="file" />
-	</condition>
+	<property name="FLEX_HOME" value="${basedir}/../flex-sdk"/>
 	<echo>FLEX_HOME is ${FLEX_HOME}</echo>