clk.c:undefined reference to `mmp_clk_register_pll'

[kbuild test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   f5e94d10e4c468357019e5c28d48499f677b284f
commit: 5d34d0b32d6c13947b0aa890fc4c68f203491169 clk: mmp2: Add support for PLL clock sources
date:   3 weeks ago
config: arm-mmp2_defconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout 5d34d0b32d6c13947b0aa890fc4c68f203491169
        # save the attached .config to linux build tree
        GCC_VERSION=9.3.0 make.cross ARCH=arm 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@xxxxxxxxx>

All errors (new ones prefixed by >>):

   arm-linux-gnueabi-ld: drivers/clk/mmp/clk.o: in function `mmp_register_pll_clks':
>> clk.c:(.text+0x4bc): undefined reference to `mmp_clk_register_pll'

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0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip