open-mpi: add option to enable Java bindings

Closes Homebrew/homebrew#49774.

Signed-off-by: Dominyk Tiller <dominyktiller@gmail.com>

Formula/open-mpi.rb

@@ -29,6 +29,7 @@ class OpenMpi < Formula
 
   depends_on :fortran => :recommended
   depends_on "libevent"
+  depends_on :java => :optional
 
   def install
     ENV.cxx11 if build.cxx11?
@@ -44,6 +45,7 @@ class OpenMpi < Formula
     args << "--with-platform-optimized" if build.head?
     args << "--disable-mpi-fortran" if build.without? "fortran"
     args << "--enable-mpi-thread-multiple" if build.with? "mpi-thread-multiple"
+    args << "--enable-mpi-java" if build.with? "java"
 
     system "./autogen.pl" if build.head?
     system "./configure", *args