build: modify build command to set MAKEFLAGS for macOS compatibility

Author: frangarcj

CMakeLists.txt

@@ -326,7 +326,7 @@ function(toolchain_deps toolchain_deps_dir toolchain_install_dir toolchain_suffi
         --enable-plugins
         --without-zstd
         "--with-pkgversion=${pkgversion}"
-        BUILD_COMMAND $(MAKE)
+        BUILD_COMMAND ${CMAKE_COMMAND} -E env $<IF:$<PLATFORM_ID:Darwin>,MAKEFLAGS=-j1,> $(MAKE)
         INSTALL_COMMAND $(MAKE) install DESTDIR=${toolchain_install_dir}
         )