clk: prima2: fix return value check in sirfsoc_of_clk_init()
clk: prima2: fix return value check in sirfsoc_of_clk_init()

In case of error, the function clk_get() returns ERR_PTR()
not NULL. The NULL test in the return value check should
be replaced with IS_ERR().

Signed-off-by: Wei Yongjun <b8f9cab8be13de37b9588aedad10a20fc3a68783@trendmicro.com.cn>
Acked-by: Barry Song <d80107dffbff3a1b0d911a6a6bd06711092a2453@gmail.com>
Signed-off-by: Mike Turquette <6dab61939fc5e23761050a66932f032dceda5ebf@linaro.org>
[6dab61939fc5e23761050a66932f032dceda5ebf@linaro.org: added missing parenthesis to fix compile break]

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs