nvmutil: rename x_i_close to close_on_eintr

that's what it does. waits for eintr to stop firing

Signed-off-by: Leah Rowe <leah@libreboot.org>

util/nvmutil/lib/num.c

@@ -80,7 +80,7 @@ rlong(void)
 	    sizeof(unsigned long), 0, IO_READ, LOOP_EAGAIN,
 	    LOOP_EINTR, MAX_ZERO_RW_RETRY, OFF_ERR);
 
-	if (x_i_close(fd) < 0)
+	if (close_on_eintr(fd) < 0)
 		err(errno, "Can't close randomness fd");
 
 	if (nr != sizeof(unsigned long))