powercap/drivers/dtpm: Fix __udivdi3 and __aeabi_uldivmod unresolved symbols

32-bit architectures do not support u64 divisions, so the macro
DIV_ROUND_CLOSEST is not adequate as the compiler will replace the
call to an unexisting function for the platform, leading to
unresolved references to symbols.

Fix this by using the compatible macros:

DIV64_U64_ROUND_CLOSEST and DIV_ROUND_CLOSEST_ULL.

Fixes: a20d0ef9 ("powercap/drivers/dtpm: Add API for dynamic thermal power management")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>