Use qt.conf to sysrootify the qmake builds

Instead of patching the qtbase sources, use the qt.conf to override
the sysrootify option for qmake.

classes/qt6-qmake.bbclass

@@ -134,6 +134,7 @@ HostSpec = ${OE_QMAKE_PLATFORM_NATIVE}
 TargetSpec = ${OE_QMAKE_PLATFORM}
 ExternalHostBinaries = ${OE_QMAKE_PATH_EXTERNAL_HOST_BINS}
 Sysroot = ${STAGING_DIR_TARGET}
+SysrootifyPrefix=true
 EOF
 }
 

recipes-qt/qt6/qtbase/0003-Sysrootify-qmake.patch

@@ -1,26 +0,0 @@
-From bc78a382df5f64f3665fe45779941aae250f50b1 Mon Sep 17 00:00:00 2001
-From: Samuli Piippo <samuli.piippo@qt.io>
-Date: Mon, 17 Feb 2020 15:33:55 +0200
-Subject: [PATCH] Sysrootify qmake
-
-For cross-compilations we need to enable qmake to sysrootify
-the install paths.
-
-Change-Id: I47d210f89203e32da59a1e41fcd6ebd28e968b25
----
- cmake/QtBuild.cmake | 2 +-
- 1 file changed, 1 insertion(+), 1 deletion(-)
-
-diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
-index 407f0b6524..4dbbe4c3ff 100644
---- a/cmake/QtBuild.cmake
-+++ b/cmake/QtBuild.cmake
-@@ -3995,7 +3995,7 @@ function(qt_generate_qconfig_cpp)
-     set(QT_CONFIG_STRS "")
- 
-     qt_add_string_to_qconfig_cpp("") # config.input.sysroot
--    qt_add_string_to_qconfig_cpp("false") # qmake_sysrootify
-+    qt_add_string_to_qconfig_cpp("true") # qmake_sysrootify
-     qt_add_string_to_qconfig_cpp("${INSTALL_BINDIR}") # TODO: Host-specific
-     qt_add_string_to_qconfig_cpp("${INSTALL_LIBDIR}") # TODO: Host-specific
-     qt_add_string_to_qconfig_cpp("${INSTALL_DATADIR}") # TODO: Host-specific

recipes-qt/qt6/qtbase_git.bb

@@ -16,7 +16,6 @@ include recipes-qt/qt6/qt6-git.inc
 SRC_URI += "\
     file://0001-Add-linux-oe-g-platform.patch \
     file://0002-qlibraryinfo-allow-to-set-qt.conf-from-the-outside-u.patch \
-    file://0003-Sysrootify-qmake.patch \
     file://0004-qtbase-allow-paths-outside-of-prefix.patch \
     file://0005-Allow-build-without-opengl.patch \
 "