All instances of BOOST_FOREACH were removed in an earlier commit, but it
was reintroduced when xtrx support was merged. I removed BOOST_FOREACH
Also, xtrx support fails to build because it relies on the
xtrx_open_list function, which was removed from the xtrx API in 2019. It
was replaced with xtrx_open_string.
I don't have xtrx hardware, so I've only tested that gr-osmosdr compiles
with these changes.
Signed-off-by: Eric Wild <firstname.lastname@example.org>