hostapd: SAE - Enable hunting-and-pecking and H2E

hostapd: SAE - Enable hunting-and-pecking and H2E

Enable both the hunting-and-pecking loop and hash-to-element mechanisms
by default in OpenWRT with SAE.

Commercial Wi-Fi solutions increasingly frequently now ship with both
hunting-and-pecking and hash-to-element (H2E) enabled by default as this
is more secure and more performant than offering hunting-and-pecking
alone for H2E capable clients.

The hunting and pecking loop mechanism is inherently fragile and prone to
timing-based side channels in its design and is more computationally
intensive to perform. Hash-to-element (H2E) is its long-term
replacement to address these concerns.

For clients that only support the hunting-and-pecking loop mechanism,
this is still available to use by default.

For clients that in addition support, or were to require, the
hash-to-element (H2E) mechanism, this is then available for use.

Signed-off-by: Nick Lowe <nick.lowe@gmail.com>