patching lang/python3* options.mk to support pgo and lto

[Peter Lai <cowbert%gmail.com@localhost>]

I've been running patched options.mk for both py36 and py37 for a
while in my local repo, looks something like this:

.if !empty(PKG_OPTIONS:Menable-optimizations)
CONFIGURE_ARGS+=        --enable-optimizations
.endif

.if !empty(PKG_OPTIONS:Mwith-lto)
CONFIGURE_ARGS+=        --with-lto
.endif

Is this something that would be supported if I tested on all py3x and
submitted the patches? Or has someone already tried it with
deleterious effects? (I have not yet encountered any with pkgsrc
py36/py37 packages that I use nor with pip-built).