[PATCH] libcss portability fixes for plan9

>From 294f0ec43f6f64765d85d2e85ac9b4dafeb0e045
From: Ori Bernstein <ori@eigenstate.org>
Date: Sun, 22 Mar 2020 18:00:34 -0700
Subject: [PATCH] portability fixes for plan9


Several changes are made here:
- Our compilers don't like double-declared enum tags, so we rename
them to avoid conflicts.
- We don't handle static initializations of bitfields, so we
replace 2 16 bit bitfields with 2 int16_ts. This shouldn't
affect storage or performance.
- uint32_t isn't guaranteed to be compatible with css_unit,
and in fact it isn't on plan9, so we need to just pass
a uint32_t.

diff -urN a/include/libcss/errors.h b/include/libcss/errors.h
--- a/include/libcss/errors.h Mon Feb 24 02:28:58 2020
+++ b/include/libcss/errors.h Sun Mar 22 18:00:34 2020
@@ -14,8 +14,9 @@