macOS: Disable CoreText shaper in Harfbuzz-NG

On macOS, we have been using a different code path internally in
Harfbuzz-NG for shaping, since most fonts on the platform are based
on AAT rather than OpenType, and this was not supported by the
OT shaper in Harfbuzz before HB 2.0.0.

However, AAT support has been added to the main shaper code now,
and is in a shape where it is used in both Chrome and Firefox,

Since we have upgraded the Harfbuzz in Qt as well as updated the
minimum required version for system-harfbuzz, we can also use this
code path and avoid another source of platform-specific issues.

Change-Id: I5cf4626d986998a0a4614c751183bcac6f4e588d
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/3rdparty/harfbuzz-ng/harfbuzz-ng.pro

@@ -179,27 +179,6 @@ contains(SHAPERS, opentype) {
         $$PWD/src/hb-ot-var.h
 }
 
-darwin {
-    DEFINES += HAVE_CORETEXT
-
-    SOURCES += \
-        $$PWD/src/hb-coretext.cc
-
-    HEADERS += \
-        $$PWD/src/hb-coretext.h
-
-    uikit {
-        # On iOS/tvOS/watchOS CoreText and CoreGraphics are stand-alone frameworks
-        LIBS_PRIVATE += -framework CoreText -framework CoreGraphics
-    } else {
-        # On Mac OS they are part of the ApplicationServices umbrella framework,
-        # even in 10.8 where they were also made available stand-alone.
-        LIBS_PRIVATE += -framework ApplicationServices
-    }
-
-    CONFIG += watchos_coretext
-}
-
 contains(SHAPERS, fallback)|isEmpty(SHAPERS) {
     DEFINES += HAVE_FALLBACK