build/win: Apply the same icu tweaks for 64 bit builds.

build/windows/jhbuild/patches/icu-fix-library-names.patch

@@ -19,3 +19,24 @@
  
  # The #M# is used to delete lines for icu-config
  # Current full path directory.
+--- a/source/config/mh-mingw64	2012-12-28 16:52:21.141964000 -0500
++++ b/source/config/mh-mingw64	2012-12-28 18:24:11.955818449 -0500
+@@ -66,16 +66,8 @@
+ LIBSICU = $(LIBPREFIX)$(STATIC_PREFIX)$(ICUPREFIX)
+ A = a
+ 
+-## An import library is needed for z/OS and MSVC
+-IMPORT_LIB_EXT = .lib
+-
+-LIBPREFIX=
+-
+-# Change the stubnames so that poorly working FAT disks and installation programs can work.
+-# This is also for backwards compatibility.
+-DATA_STUBNAME = dt
+-I18N_STUBNAME = in
+-LIBICU = $(STATIC_PREFIX_WHEN_USED)$(ICUPREFIX)
++## import libraries are nice to have under mingw
++IMPORT_LIB_EXT = .dll.a
+ 
+ # The #M# is used to delete lines for icu-config
+ # Current full path directory.