pgsql: In transam.h,don't expose static inline functions to frontend c

In transam.h, don't expose static inline functions to frontend code.

That leads to unsatisfied external references if the C compiler fails
to elide unused static functions.  Apparently, we have no buildfarm
members building HEAD that have that issue ... but such compilers still
exist in the wild.  Need to do something about that.

In passing, fix Berkeley-era typo in comment.

Discussion: https://postgr.es/m/27054.1558533367@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4fbf809e13c3ba09c4f03d148cb58767e56f67f1

Modified Files
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src/include/access/transam.h | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)