pgsql: Fix -Wstrict-prototypes warning in ecpg_init_sqlca() declaration

Fix -Wstrict-prototypes warning in ecpg_init_sqlca() declaration.

When headerscheck compiles ecpglib_extern.h, POSTGRES_ECPG_INTERNAL is
not defined, causing sqlca.h to expand "sqlca" as a macro
(*ECPGget_sqlca()). This causes the ecpg_init_sqlca() declaration to
trigger a -Wstrict-prototypes warning.

Fix by renaming the parameter from "sqlca" to "sqlca_p" in both the
declaration and definition, avoiding the macro expansion.

Author: Bertrand Drouvot <bertranddrouvot(dot)pg(at)gmail(dot)com>
Reported-by: Nazir Bilal Yavuz <byavuz81(at)gmail(dot)com>
Diagnosed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/CAN55FZ1VDwJ-ZD092ChYf%2B%2BhuP%2B-S3Cg45tJ8jNH5wx2c4BHAg%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f91b8ff6af910744e6e317c5c2bc2698addde59a

Modified Files
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src/interfaces/ecpg/ecpglib/ecpglib_extern.h | 2 +-
src/interfaces/ecpg/ecpglib/misc.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)