[tlbuild] Patch for icu

[Ken Brown]

The latest icu in the TL trunk doesn't build on Cygwin.  The following 
patch to icu-49.1/common/putil.cpp fixes it:

--- putil.cpp.orig      2012-03-22 10:40:56.000000000 -0400
+++ putil.cpp   2012-03-22 21:23:14.430718000 -0400
@@ -2181,7 +2181,7 @@

  #endif

-#elif U_PLATFORM_HAS_WIN32_API
+#elif U_PLATFORM_USES_ONLY_WIN32_API

  U_INTERNAL void * U_EXPORT2
  uprv_dl_open(const char *libName, UErrorCode *status) {


Without this patch, the build fails as follows:

/home/kbrown/src/texlive/test/Work/libs/icu/../../../libs/icu/icu-49.1/common/putil.cpp: 
In function 'void* uprv_dl_open_49(const char*, UErrorCode*)':
/home/kbrown/src/texlive/test/Work/libs/icu/../../../libs/icu/icu-49.1/common/putil.cpp:2188:3: 
error: 'HMODULE' was not declared in this scope

The patch is consistent with what's done at other places in the file 
where HMODULE occurs; it's also consistent with icu-4.8.

Ken