pgsql: Disable extended alignment uses on older g++

Disable extended alignment uses on older g++

Fix for commit a9bdb63bba8. The previous plan of redefining alignas
didn't work, because it interfered with other C++ header files (e.g.,
LLVM). So now the new workaround is to just disable the affected
typedefs under the affected compilers. These are not typically used
in extensions anyway.

Discussion: /messages/by-id/3119480.1769189606@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/6ceef9408c26b6e188ec88c4303e9bad8ce33bff

Modified Files
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src/include/c.h | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)