Avoid some warnings in rdoff/rdf2bin.c

I received some warnings when running make on the head revision of
nasm from git:

----
rdf2bin.c: In function 'main':
rdf2bin.c:122: warning: comparison between signed and unsigned
rdf2bin.c:123: warning: comparison between signed and unsigned
rdf2bin.c:124: warning: comparison between signed and unsigned
----

I think these warnings are innocuous and should be safely avoidable
with simple casts (please see attached patch).

* rdoff/rdf2bin.c
(main): cast to size_t for comparison with fwrite return value

Signed-off-by: Bo Borgerson <gigabo@gmail.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/rdoff/rdf2bin.c b/rdoff/rdf2bin.c
index 7140b2b..c23b18c 100644
--- a/rdoff/rdf2bin.c
+++ b/rdoff/rdf2bin.c
@@ -119,9 +119,9 @@ int main(int argc, char **argv)
         return 1;
     }
 
-    if (fwrite(m->t, 1, m->f.seg[0].length, of) != m->f.seg[0].length ||
-        fwrite(padding, 1, codepad, of) != codepad ||
-        fwrite(m->d, 1, m->f.seg[1].length, of) != m->f.seg[1].length) {
+    if (fwrite(m->t, 1, m->f.seg[0].length, of) != (size_t)m->f.seg[0].length ||
+        fwrite(padding, 1, codepad, of) != (size_t)codepad ||
+        fwrite(m->d, 1, m->f.seg[1].length, of) != (size_t)m->f.seg[1].length) {
         fprintf(stderr, "rdf2bin: error writing to %s\n", *argv);
         return 1;
     }