tomoyo: Omit use of bin2c

tomoyo: Omit use of bin2c

bin2c was, as its name implies, introduced to convert a binary file to
C code.

However, I did not see any good reason ever for using this tool because
using the .incbin directive is much faster, and often results in simpler
code.

Most of the uses of bin2c have been killed, for example:

  - 13610aa908dc ("kernel/configs: use .incbin directive to embed config_data.gz")
  - 4c0f032d4963 ("s390/purgatory: Omit use of bin2c")

security/tomoyo/Makefile has even less reason for using bin2c because
the policy files are text data. So, sed is enough for converting them
to C string literals, and what is nicer, generates human-readable
builtin-policy.h.

This is the last user of bin2c. After this commit lands, bin2c will be
removed.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
[penguin-kernel: Update sed script to also escape backslash and quote ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>