gallium/aux/tgsi/tgsi_dump.c: Fix warnings

tgsi_dump.c: In function 'iter_property':
tgsi_dump.c:443:18: warning: comparison between signed and unsigned
integer expressions [-Wsign-compare]
    for (i = 0; i < prop->Property.NrTokens - 1; ++i) {
                  ^
tgsi_dump.c:459:13: warning: comparison between signed and unsigned
integer expressions [-Wsign-compare]
       if (i < prop->Property.NrTokens - 2)

Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
Signed-off-by: Jakob Bornecrantz <jakob@collabora.com>

src/gallium/auxiliary/tgsi/tgsi_dump.c

@@ -448,7 +448,7 @@ iter_property(
    struct tgsi_iterate_context *iter,
    struct tgsi_full_property *prop )
 {
-   unsigned i;
+   int i;
    struct dump_ctx *ctx = (struct dump_ctx *)iter;
 
    TXT( "PROPERTY " );