select.mk: Tune ccache options

With these adjustments, cached object files can now be shared across
multiple Android trees on a single workstation:

* Compiler binary modification time no longer causes cache misses,
  as a hash of the compiler binary is taken rather than looking
  at the mtime and size
* Header file modification time no longer causes cache misses,
  the headers are now always hashed
* Macros such as __DATE__ and __TIME__ no longer cause cache misses
* All paths in preprocessed source (due to use of -g) are now relative

These options require ccache 3.1 or later to be used; ccache 2.4 will
ignore these.

Change-Id: I7839637e9dacf7240bd9b7bfaa6406b1db423560
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>