No need to restrict optimization to -O1 level

Works fine with -O2 as far as I see. At least with current Xcode.

Change-Id: Id28e1bb905efffa3e3b548eb34f3455c8a021f63
Reviewed-on: https://gerrit.libreoffice.org/53041Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tor Lillqvist <tml@collabora.com>

solenv/gbuild/platform/macosx.mk

@@ -22,8 +22,6 @@ export VCL_HIDE_WINDOWS=1
 
 gb_SDKDIR := $(MACOSX_SDK_PATH)
 
-gb_COMPILEROPTFLAGS := -O1
-
 include $(GBUILDDIR)/platform/com_GCC_defs.mk
 
 # Darwin mktemp -t expects a prefix, not a pattern