cobol: Eliminate padding bytes from cbl_declarative_t. [PR119377]

cobol: Eliminate padding bytes from cbl_declarative_t. [PR119377]

By changing the type of a variable in the cbl_declarative_t structure from "bool"
to "uint32_t", three uninitialized padding bytes were turned into initialized
bytes.  This eliminates the valgrind error caused by those uninitialized values.

This is an interim fix, which expediently eliminates the valgrind problem. The
underlying design flaw, which involves turning a host-side C++ structure into
a run-time data block, is slated for complete replacement in the next few weeks.

libgcobol/ChangeLog:

	PR cobol/119377
	* common-defs.h: (struct cbl_declaratives_t): Change "bool global" to
	"uint32_t global".

(cherry picked from commit d7d24f9cc55d5cf0a70a984d4e63e8a307710d9e)