[tlbuild] Broken TL build

[Mojca Miklavec]

On Mon, 17 Jan 2022 at 22:34, Karl Berry wrote:
>
>     libs/icu/icu-src/source/i18n/plurrule.cpp:1884:90: error:
>     call of overloaded 'pow(int, const int32_t&)' is ambiguous
>
> I hope you (or someone) can figure out what to do about that one ... -k

I didn't yet try the full build, but in an isolated environment
changing pow(10, exponent) into pow(10.0, exponent) helps.

The expression with an integer base should be valid C++11, but
according to the docs it gets cast to double anyway, so there's no
efficiency benefit in using an integer base.

Mojca