subsurface: 4.5.97 -> 4.6.0 (#22615)

We do a few more things:

 - libmarble and libdivecomputer with the subsurface patches have both been
   inlined for 2 reasons:
   a) nobody else is using these forks
   b) they need to be updated in lockstep with subsurface

 - instead of building libmarble against qtquick1, we now build using
   qtquickcontrols (qtquick2)

 - getting rid of qtquick1 also allows us to use the default qt (currently 5.6)

 - we get rid of some hacks to deal with library dependencies

 - instead of manually overriding various phases, we simply use cmakeFlags to
   pass proper parameters