LXQt about dialog.

mkdir /data/buildroot/package/lxqt-about
cat > /data/buildroot/package/lxqt-about/Config.in<< 'EOF'
config BR2_PACKAGE_LXQT_ABOUT
        bool "lxqt-about"
        depends on BR2_PACKAGE_QT5BASE
        depends on BR2_PACKAGE_LIBLXQT
        depends on BR2_PACKAGE_QT5TOOLS
        depends on BR2_PACKAGE_LXQT_BUILD_TOOLS
        depends on BR2_PACKAGE_PCRE
        depends on BR2_PACKAGE_QT5TOOLS
        help
          LXQt about dialog.
EOF

cat > /data/buildroot/package/lxqt-about/lxqt-about.mk<< 'EOF'
#############################################################
#
# lxqt-about
#https://github.com/lxqt/lxqt-about/archive/refs/tags/1.1.0.tar.gz
#############################################################
LXQT_ABOUT_VERSION = 1.1.0
LXQT_ABOUT_SOURCE  = $(LXQT_ABOUT_VERSION).tar.gz
LXQT_ABOUT_SITE    = https://github.com/lxqt/lxqt-about/archive/refs/tags

LXQT_ABOUT_DEPENDENCIES = liblxqt qt5tools lxqt-build-tools qt5tools
LXQT_ABOUT_INSTALL_TARGET = YES
LXQT_ABOUT_SUPPORTS_IN_SOURCE_BUILD = NO 
LXQT_ABOUT_CONF_OPTS = -DCMAKE_TOOLCHAIN_FILE=$(HOST_DIR)/share/buildroot/toolchainfile.cmake \
    -Dlxqt_DIR=$(TARGET_DIR)/usr/share/cmake/lxqt \
    -Dlxqt-build-tools_DIR=$(TARGET-DIR)/usr/share/cmake/lxqt-build-tools \
    -DQt5Xdg_DIR=$(TARGET_DIR)/usr/share/cmake/qt5xdg \
    -DQt5XdgIconLoader_DIR=$(TARGET_DIR)/usr/share/cmake/qt5xdgiconloader \
    -DKF5WindowSystem_DIR=$(TARGET_DIR)/usr/lib/cmake/KF5WindowSystem \
    -Dfm-qt_DIR=$(TARGET_DIR)/usr/share/cmake/fm-qt \
    -DCMAKE_INSTALL_PREFIX=/usr

define LXQT_ABOUT_CONFIGURE_CMDS
  if [[ ! -L "$(HOST_DIR)/usr/lib/libpcre.so.3" ]]; then ln -s $(HOST_DIR)/usr/lib/libpcre.so $(HOST_DIR)/usr/lib/libpcre.so.3; fi
  if [[ ! -d $(@D)/buildroot-build ]]; then mkdir $(@D)/buildroot-build; fi
  cd $(@D)/buildroot-build && \
  XCB_INCLUDE_DIR="$(TARGET_DIR)/usr/lib" LDFLAGS="$(LDFLAGS) -pthread -Wl,--as-needed -Wl,--allow-shlib-undefined" cmake "$(@D)/" $(LXQT_ABOUT_CONF_OPTS)
endef

$(eval $(cmake-package))
EOF

sed -i '/menu "Custom packages"/a source "package/lxqt-about/Config.in"' /data/buildroot/package/Config.in