Upgrade to libvips v8.15.2 (#225)

LIBVIPS_VERSION

@@ -1 +1 @@
-8.15.1
+8.15.2

build/lin.sh

@@ -457,7 +457,7 @@ CFLAGS="${CFLAGS} -O3" meson setup _build --default-library=static --buildtype=r
 meson install -C _build --tag devel
 
 mkdir ${DEPS}/vips
-$CURL https://github.com/libvips/libvips/releases/download/v${VERSION_VIPS}/vips-$(without_prerelease $VERSION_VIPS).tar.xz | tar xJC ${DEPS}/vips --strip-components=1
+$CURL https://github.com/libvips/libvips/releases/download/v${VERSION_VIPS}a/vips-$(without_prerelease $VERSION_VIPS).tar.xz | tar xJC ${DEPS}/vips --strip-components=1
 cd ${DEPS}/vips
 # Link libvips.so.42 statically into libvips-cpp.so.42
 sed -i'.bak' "s/library('vips'/static_&/" libvips/meson.build
@@ -475,7 +475,7 @@ fi
 # Disable building man pages, gettext po files, tools, and (fuzz-)tests
 sed -i'.bak' "/subdir('man')/{N;N;N;N;d;}" meson.build
 CFLAGS="${CFLAGS} -O3" CXXFLAGS="${CXXFLAGS} -O3" meson setup _build --default-library=shared --buildtype=release --strip --prefix=${TARGET} ${MESON} \
-  -Ddeprecated=false -Dintrospection=disabled -Dmodules=disabled -Dcfitsio=disabled -Dfftw=disabled -Djpeg-xl=disabled \
+  -Ddeprecated=false -Dexamples=false -Dintrospection=disabled -Dmodules=disabled -Dcfitsio=disabled -Dfftw=disabled -Djpeg-xl=disabled \
   ${WITHOUT_HIGHWAY:+-Dhighway=disabled} -Dorc=disabled -Dmagick=disabled -Dmatio=disabled -Dnifti=disabled -Dopenexr=disabled \
   -Dopenjpeg=disabled -Dopenslide=disabled -Dpdfium=disabled -Dpoppler=disabled -Dquantizr=disabled \
   -Dppm=false -Danalyze=false -Dradiance=false \