graphics/qgis-ltr: Disable usage of ccache

If ccache is used, the build breaks with
ccache: error: unknown configuration option "compiler_type"

PR:		284996
Reported by:	Martin Birgmeier <d8zNeCFG@aon.at>

graphics/qgis-ltr/Makefile

 PORTNAME=	qgis
 DISTVERSION=	3.40.4
+PORTREVISION=	1
 CATEGORIES=	graphics geography
 MASTER_SITES=	https://qgis.org/downloads/
 PKGNAMESUFFIX=	-ltr
@@ -137,7 +138,7 @@ CMAKE_ARGS+=	-DCMAKE_BUILD_TYPE:STRING=Release \
 CMAKE_ON=	USE_OPENCL WITH_3D WITH_ASTYLE WITH_BINDINGS WITH_COPC \
 		WITH_CUSTOM_WIDGETS WITH_DRACO WITH_EPT WITH_INTERNAL_LAZPERF \
 		WITH_POSTGRESQL WITH_QTWEBENGINE
-CMAKE_OFF=	ENABLE_TESTS WITH_INTERNAL_MDAL WITH_QTWEBKIT WITH_QWTPOLAR
+CMAKE_OFF=	ENABLE_TESTS USE_CCACHE WITH_INTERNAL_MDAL WITH_QTWEBKIT WITH_QWTPOLAR
 
 # math/pdal fails in pdal_wrench() with "undefined reference to symbol 'pthread_create@@FBSD_1.0'"
 #CXXFLAGS+=	-pthread