build, qt: Force bootstrap while building linguist tools

Qt lrelease tool depends on the xml module. This change guarantees that
it is always available after being bootstrapped.

depends/packages/qt.mk

@@ -66,6 +66,7 @@ $(package)_config_opts += -no-system-proxies
 $(package)_config_opts += -no-use-gold-linker
 $(package)_config_opts += -nomake examples
 $(package)_config_opts += -nomake tests
+$(package)_config_opts += -nomake tools
 $(package)_config_opts += -opensource
 $(package)_config_opts += -pkg-config
 $(package)_config_opts += -prefix $(host_prefix)