Fix build under LLVM15

Fix many -Wint-conversion errors such as the example below, including
an aso atomics error.

connect.c:87:12: error: incompatible pointer to integer conversion initializing 'LONG' (aka 'int') with an expression of type 'void *' [-Wint-conversion]
   DB_ADDR mdba = NULL;   /* db address of current member record */
           ^      ~~~~

cde/lib/DtHelp/AccessCCDF.c

@@ -59,6 +59,8 @@
 extern int errno;
 #endif
 
+extern char *_DtHelpGetLocale(void);
+
 /*
  * Canvas Engine includes
  */