wam: fix surface type name in application manifest

wam: fix surface type name in application manifest

Renamed appinfo.json field surface_role to be surface_type to be
consistent with other parts of the code base. Took the chance to remove
types that were not meaningful, and renamed default type (the one used
when it is not set) to be default instead of none.

Then updated the only applications setting the value to use the new
propery. Those are html5-background and html5-homescreen.

wam: 8ea41f7..4fbd6e6
4fbd6e6 [op][agl][wayland] Provide only supported AGL shell types

html5-background: e91be22..aa7e2a8
aa7e2a8 Rename surface/role in appinfo.json to surface/type.
bb4f497 autobuild: Remove autobuild scripts

html-homescreen: fc0ffa4..f3cecb6
f3cecb6 Rename surface/role in appinfo.json to surface/type.

Bug-AGL: SPEC-4505
Signed-off-by: Jose Dapena Paz <jdapena@igalia.com>
Change-Id: I404717dd5d848220bd5f070b98de56df38a78e20