Set default file encoding to prevent java compiler warnings

* The keymap files have UTF-8 characters embedded in comments.
  javac complains about this unless the default encoding is set.
diff --git a/contrib/packages/rpm/el5/SPECS/tigervnc.spec b/contrib/packages/rpm/el5/SPECS/tigervnc.spec
index b2ff917..e3656d4 100644
--- a/contrib/packages/rpm/el5/SPECS/tigervnc.spec
+++ b/contrib/packages/rpm/el5/SPECS/tigervnc.spec
@@ -1128,7 +1128,7 @@
 # Build Java applet
 pushd java
 %{cmake28} .
-LANG=C make
+JAVA_TOOL_OPTIONS="-Dfile.encoding=UTF8" make
 popd
 
 %install
diff --git a/contrib/packages/rpm/el6/SPECS/tigervnc.spec b/contrib/packages/rpm/el6/SPECS/tigervnc.spec
index 034467a..66daf8f 100644
--- a/contrib/packages/rpm/el6/SPECS/tigervnc.spec
+++ b/contrib/packages/rpm/el6/SPECS/tigervnc.spec
@@ -219,7 +219,7 @@
 # Build Java applet
 pushd java
 %{cmake28} .
-make
+JAVA_TOOL_OPTIONS="-Dfile.encoding=UTF8" make
 popd
 
 %install
diff --git a/contrib/packages/rpm/sle11/SPECS/tigervnc.spec b/contrib/packages/rpm/sle11/SPECS/tigervnc.spec
index ddf9310..e601d71 100644
--- a/contrib/packages/rpm/sle11/SPECS/tigervnc.spec
+++ b/contrib/packages/rpm/sle11/SPECS/tigervnc.spec
@@ -324,7 +324,7 @@
 # Build java client
 pushd java
 cmake -DCMAKE_INSTALL_PREFIX:PATH=%{_prefix}
-make %{?_smp_mflags}
+JAVA_TOOL_OPTIONS="-Dfile.encoding=UTF8" make %{?_smp_mflags}
 popd
 
 %install