pgsql: Use OpenSSL-specific ifdefs in sha2.h

Use OpenSSL-specific ifdefs in sha2.h

In order to separate OpenSSL's SHA symbols, this header has been using
USE_SSL, which is equivalent to USE_OPENSSL.  There is now only one SSL
implementation included in the tree, so this works fine, but when
adding a new SSL implementation this would run into failures.

Author: Daniel Gustafsson
Discussion: https://postgr.es/m/0DF29010-CE26-4F51-85A6-9C8ABF5536F9@yesql.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/96719e52b1abd3a8c712d06a809b7e6c97c2e3a0

Modified Files
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src/include/common/sha2.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)