NFC: trf7970a: fix check of clock frequencies, use && instead of ||

The "or" condition (clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
(clk_freq != TRF7970A_13MHZ_CLOCK_FREQUE) will always be true because
clk_freq cannot be equal to two different values at the same time. Use
the  && operator instead of || to fix this.

Detected by CoverityScan, CID#1430468 ("Constant expression result")

Fixes: 837eb4d21ecde7 ("NFC: trf7970a: add device tree option for 27MHz clock")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Geoff Lansberry <geoff@kuvee.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/nfc/trf7970a.c

@@ -2059,7 +2059,7 @@ static int trf7970a_probe(struct spi_device *spi)
 	}
 
 	of_property_read_u32(np, "clock-frequency", &clk_freq);
-	if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) ||
+	if ((clk_freq != TRF7970A_27MHZ_CLOCK_FREQUENCY) &&
 	    (clk_freq != TRF7970A_13MHZ_CLOCK_FREQUENCY)) {
 		dev_err(trf->dev,
 			"clock-frequency (%u Hz) unsupported\n", clk_freq);