pgsql: Avoid possible crash within libsanitizer.

Avoid possible crash within libsanitizer.

We've successfully used libsanitizer for awhile with the undefined
and alignment sanitizers, but with some other sanitizers (at least
thread and hwaddress) it crashes due to internal recursion before
it's fully initialized itself.  It turns out that that's due to the
"__ubsan_default_options" hack installed by commit f686ae82f, and we
can fix it by ensuring that __ubsan_default_options is built without
any sanitizer instrumentation hooks.

Reported-by: Emmanuel Sibi <emmanuelsibi.mec@gmail.com>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: Emmanuel Sibi <emmanuelsibi.mec@gmail.com>
Fix-suggested-by: Jacob Champion <jacob.champion@enterprisedb.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/F7543B04-E56C-4D68-A040-B14CCBAD38F1@gmail.com
Discussion: https://postgr.es/m/dbf77bf7-6e54-ed8a-c4ae-d196eeb664ce@gmail.com
Backpatch-through: 16

Branch
------
REL_17_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/a9515f294de153360e58d17a9aa468532cbab7e5

Modified Files
--------------
src/backend/main/main.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)