Add libwinpthread-1.dll to windows sdk, copied from clang-r365631b

lld.exe depends on this library.

Bug: 148267171
Bug: 142590626
Bug: 144040336

Test: (gLinux) m TARGET_PRODUCT=sdk_phone_armv7 TARGET_BUILD_VARIANT=userdebug sdk dist sdk_repo
      (gLinux) m TARGET_PRODUCT=sdk_phone_armv7 TARGET_BUILD_VARIANT=userdebug win_sdk dist sdk_repo
Change-Id: I53ff5f9769aa527cd340bc08cb494005428fc646
1 file changed