Fixes gcc '-Wunused-but-set-variable' warning:
drivers/staging/sm750fb/ddk750_chip.c: In function set_chip_clock:
drivers/staging/sm750fb/ddk750_chip.c:59:15: warning: variable actual_mx_clk set but not used [-Wunused-but-set-variable]
It is not used since commit 
f0977109a577 ("staging:
sm750fb: lower case to fix camelcase checkpatch warning")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/1570520515-2186-4-git-send-email-zhengbin13@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 static void set_chip_clock(unsigned int frequency)
 {
        struct pll_value pll;
-       unsigned int actual_mx_clk;
 
        /* Cheok_0509: For SM750LE, the chip clock is fixed. Nothing to set. */
        if (sm750_get_chip_type() == SM750LE)
                 * Return value of sm750_calc_pll_value gives the actual
                 * possible clock.
                 */
-               actual_mx_clk = sm750_calc_pll_value(frequency, &pll);
+               sm750_calc_pll_value(frequency, &pll);
 
                /* Master Clock Control: MXCLK_PLL */
                poke32(MXCLK_PLL_CTRL, sm750_format_pll_reg(&pll));