Merge bitcoin/bitcoin#32496: depends: drop ltcg for Windows Qt

9653ebc depends: remove support for Windows Qt LTO builds (fanquake)

Pull request description:

  The related Windows patches were dropped in 5e794e6, and "Cross-compiling does not support LTO." (from #30997).

ACKs for top commit:
  maflcko:
    lgtm ACK 9653ebc

Tree-SHA512: 40ae7b17669bf87f2e848055e85e1a6c946f0bb0bc1674e18f1622ec4a0613fe955a4daf83928c9375035dac289ce2a72dd7f347b15f86d108157f9da9499945

Author: fanquake

depends/packages/qt.mk

@@ -150,9 +150,6 @@ endif
 $(package)_config_opts_mingw32 := -no-dbus
 $(package)_config_opts_mingw32 += -no-freetype
 $(package)_config_opts_mingw32 += -no-pkg-config
-ifneq ($(LTO),)
-$(package)_config_opts_mingw32 += -ltcg
-endif
 
 # CMake build options.
 $(package)_config_env := CC="$$($(package)_cc)"