boost: Add zstd as a dependency to boost

Depends on PR #7126

With this change:
eb03aa43b9
boost iostreams supports zstd compression. If the zstd package is  built
before boost, then the packaging step complains that libzstd.so is not
packaged.

Build Tested: PR #7876 used to fail CI without this, now it passes.

Signed-off-by: Amol Bhave <ambhave@fb.com>

libs/boost/Makefile

@@ -342,7 +342,7 @@ $(eval $(call DefineBoostLibrary,date_time,,))
 $(eval $(call DefineBoostLibrary,fiber,coroutine filesystem,,!boost-fiber-exclude))
 $(eval $(call DefineBoostLibrary,filesystem,system,))
 $(eval $(call DefineBoostLibrary,graph,regex,))
-$(eval $(call DefineBoostLibrary,iostreams,,+zlib +liblzma +libbz2))
+$(eval $(call DefineBoostLibrary,iostreams,,+zlib +liblzma +libbz2 +zstd))
 $(eval $(call DefineBoostLibrary,locale,system,$(ICONV_DEPENDS),BUILD_NLS))
 $(eval $(call DefineBoostLibrary,log,system chrono date_time thread filesystem regex,))
 $(eval $(call DefineBoostLibrary,math,,))