Prefer PCRE2POSIX_SHARED to PCRE2_STATIC for pcre2posix (#310)

Since a8a875e (windows: integrate visibility attributes without
conflicts (#249), 2023-05-16), the use of PCRE2_STATIC has been
deprecated so set PCRE2POSIX_SHARED instead when relevant.

Author: carenas

pcre2-config.in

@@ -79,7 +79,7 @@ while test $# -gt 0; do
         if test @includedir@ != /usr/include ; then
           includes=-I@includedir@
         fi
-        echo $includes @PCRE2_STATIC_CFLAG@
+        echo $includes @PCRE2POSIX_CFLAG@
       else
         echo "${usage}" 1>&2
       fi

src/pcre2posix.h

@@ -9,7 +9,7 @@ POSIX wrapper interface.
 
                        Written by Philip Hazel
      Original API code Copyright (c) 1997-2012 University of Cambridge
-          New API code Copyright (c) 2016-2022 University of Cambridge
+          New API code Copyright (c) 2016-2023 University of Cambridge
 
 -----------------------------------------------------------------------------
 Redistribution and use in source and binary forms, with or without
@@ -132,7 +132,6 @@ set, we ensure here that it has no effect. */
 #define PCRE2_CALL_CONVENTION
 #endif
 
-
 #ifndef PCRE2_EXPORT
 #define PCRE2_EXPORT
 #endif