valgrind: fix call/cachegrind ptests

valgrind: fix call/cachegrind ptests

Use the *_annotate executables from ${bindir}

Actually install cachegrind/tests/a.c since it is used by
the call/cachegrind/tests/ann[12].vgtest files.

With this change and the previous commits, the ptest results
on qemux86-64 when invoked with:
    runqemu qemux86 kvm nographic slirp qemuparams="-m 2048"
are:

=== Test Summary ===
TOTAL: 159
PASSED: 149
FAILED: 1
SKIPPED: 9

Only drd/tests/pth_detached3 remains to be fixed.

Signed-off-by: Randy MacLeod <Randy.MacLeod@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>