af-binder: Extend maxlength of websocket messages

af-binder: Extend maxlength of websocket messages

The default maxlength of 65000 bytes is too limited.
This commit extends the maxlength to 1048500 bytes.

Bug-AGL: SPEC-981

Change-Id: I75963077d9d151eb9b1b81acbbd3a32272bd0976
Signed-off-by: José Bollo <jose.bollo@iot.bzh>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/11489
Tested-by: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-build: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
ci-image-boot-test: Jenkins Job builder account <agl-jobbuilder@automotivelinux.org>
Reviewed-by: Matt Ranostay <matt.ranostay@konsulko.com>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>