hostapd: fix Argument list too long build error
Currently, both CI and local builds of wpa-supplicant will fail with:
/bin/sh: Argument list too long
Its happening as the argument list for mkdir in build.rules is too large
and over the MAX_ARG_STRLEN limit.
It seems that recent introduction of APK compatible version schema has
increased the argument size and thus pushed it over the limit uncovering
the issue.
Fixes: e8725a932e16 ("treewide: use APK compatible version schema")
Signed-off-by: Robert Marko <robimarko@gmail.com>