util: make mesa-sha1.c completely empty when there are no SHA1 impls

My earlier attempt to fix this missed the fact that there was a #else
clause that assumes that you have openssh. This moves the whole thing
under #ifdef HAVE_SHA1 which should avoid this issue.

Fixes: 13bfa5201 (util: always include sha1 into the build)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91898
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Dave Airlie <airlied@gmail.com>

src/util/mesa-sha1.c

@@ -26,6 +26,8 @@
 
 #include "mesa-sha1.h"
 
+#ifdef HAVE_SHA1
+
 #if defined(HAVE_SHA1_IN_LIBMD)  /* Use libmd for SHA1 */ \
 	|| defined(HAVE_SHA1_IN_LIBC)   /* Use libc for SHA1 */
 
@@ -290,8 +292,6 @@ _mesa_sha1_final(struct mesa_sha1 *ctx, unsigned char result[20])
 
 #endif
 
-#ifdef HAVE_SHA1
-
 void
 _mesa_sha1_compute(const void *data, size_t size, unsigned char result[20])
 {