Don't always error if a debug program fails

This is often expected, and the calling code should decide whether to
emit an error or not.

Change-Id: Ic21f38b4c75f01e6b40034fdc60dde6ba7a55f4a

src/target/riscv/program.c

@@ -64,7 +64,7 @@ int riscv_program_exec(struct riscv_program *p, struct target *t)
 		return ERROR_FAIL;
 
 	if (riscv_execute_debug_buffer(t) != ERROR_OK) {
-		LOG_ERROR("Unable to execute program %p", p);
+		LOG_DEBUG("Unable to execute program %p", p);
 		return ERROR_FAIL;
 	}