[MIPS] Yosemite: Fix modpost warnings.

  MODPOST vmlinux
WARNING: arch/mips/pmc-sierra/yosemite/built-in.o(.text+0x974): Section mismatch: reference to .init.data: (between 'prom_boot_secondary' and 'prom_cpus_done')
WARNING: arch/mips/pmc-sierra/yosemite/built-in.o(.text+0x980): Section mismatch: reference to .init.data: (between 'prom_boot_secondary' and 'prom_cpus_done')
WARNING: arch/mips/pmc-sierra/yosemite/built-in.o(.text+0x978): Section mismatch: reference to .init.data: (between 'prom_boot_secondary' and 'prom_cpus_done')
WARNING: arch/mips/pmc-sierra/yosemite/built-in.o(.text+0x984): Section mismatch: reference to .init.data: (between 'prom_boot_secondary' and 'prom_cpus_done')
WARNING: arch/mips/pmc-sierra/yosemite/built-in.o(.text+0x98c): Section mismatch: reference to .init.data: (between 'prom_boot_secondary' and 'prom_cpus_done')
WARNING: arch/mips/pmc-sierra/yosemite/built-in.o(.text+0x990): Section mismatch: reference to .init.data: (between 'prom_boot_secondary' and 'prom_cpus_done')

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>