tools/power turbostat: fix leak of file descriptor on error return path

Currently the error return path does not close the file fp and leaks
a file descriptor. Fix this by closing the file.

Fixes: 5ea7647b ("tools/power turbostat: Warn on bad ACPI LPIT data")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

tools/power/x86/turbostat/turbostat.c

@@ -2944,6 +2944,7 @@ int snapshot_sys_lpi_us(void)
 	if (retval != 1) {
 		fprintf(stderr, "Disabling Low Power Idle System output\n");
 		BIC_NOT_PRESENT(BIC_SYS_LPI);
+		fclose(fp);
 		return -1;
 	}
 	fclose(fp);