tls_common.c: prevent max_early_data overflow in rlayer_early_data_count_ok()

tls_common.c: prevent max_early_data overflow in rlayer_early_data_count_ok()

Make the local max_early_data variable uint64_t so an overflow
cannot occur if the max_early_data field in the record layer struct
has the maximum value: UNT32_MAX (0xFFFFFFFF).

Resolves: https://github.com/openssl/openssl/issues/31533

Reviewed-by: Eugene Syromiatnikov <esyr@openssl.org>
Reviewed-by: Frederik Wedel-Heinen <fwh.openssl@gmail.com>
Reviewed-by: Tim Hudson <tjh@openssl.org>
MergeDate: Sun Jun 21 23:50:02 2026
(Merged from https://github.com/openssl/openssl/pull/31538)