spi/amba-pl022: fixing compilation warning.

clk_freq is used uninitialized in pl022_setup routine. This patch
fix compilation warning for using uninitialized variable

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/spi/amba-pl022.c

@@ -1795,7 +1795,7 @@ static int pl022_setup(struct spi_device *spi)
 {
 	struct pl022_config_chip const *chip_info;
 	struct chip_data *chip;
-	struct ssp_clock_params clk_freq;
+	struct ssp_clock_params clk_freq = {0, };
 	int status = 0;
 	struct pl022 *pl022 = spi_master_get_devdata(spi->master);
 	unsigned int bits = spi->bits_per_word;