Revert "remove support for HWC < 1.0"

This partially reverts commit 30bcc61431d8e3bef779472dd52a7b156dcaba09
and updates to the current API. Tested on 0.1 blobs from Tegra2/3
and OMAP3/4

Change-Id: I1a1aae0bbcc6bcc78c3400c4f79375e2233a9e4f
SurfaceFlinger: Change to support framebuffer flip for 2D blitters

- Surfaceflinger does not flip framebuffers when there are
  no layers marked for HWC_FRAMEBUFFER
- This change checks for the HWC_BLIT flag and will request a flip
  to a new FB_TARGET buffer even if there are no FRAMEBUFFER layers

Change-Id: I1cb44389a05c9ec049d7f0d39c288feccb11a91c