ANDROID: Add a tracepoint for mapping inode to full path

This will be used by eBPF and the iorapd project for high speed
inode/dev numbers to file path lookup. Look at the inodemap CL for more
details about of eBPF and iorapd using the tracepoint.

This is planned to be used by the inodemap BPF program. Also, ART folks
have been using this tracepoint for debugging "unknown inode numer"
issues.

The tracepoint will be out of tree, and not sent upstream, since VFS
developers don't accept tracepoints strictly.

Test: Run "find /" command in emulator and measure completion time
with/without treacepoint. find does a flood of lookups which stresses
the tracepoint. No performance change observed.
Test: eBPF prototypes (wip) successfully read data from the tracepoint.

OOT Bug: 139663736
Bug: 135143784
Bug: 137393447
Change-Id: I657f374659673a9c8853530d73c0622dbdbab146
Signed-off-by: Joel Fernandes <joelaf@google.com>