std.crypto.chacha: remove the hack for ChaCha with a 64-bit counter (#15818)

Support for 64-bit counters was a hack built upon the version with
a 32-bit counter, that emulated a larger counter by splitting the
input into large blocks.

This is fragile, particularily if the initial counter is set to
a non-default value and if we have parallelism.

Simply add a comptime parameter to check if we have a 32 bit or a
64 bit counter instead.

Also convert a couple while() loops to for(), and change @panic()
to @compileError().

0 files changed, 0 insertions, 0 deletions