Fix some warnings about deprecated guile functions.

[David Hampton]

Log Message:
-----------
Fix some warnings about deprecated guile functions.

Modified Files:
--------------
    gnucash/src/business/business-reports:
        business-reports.scm
    gnucash/src/report/report-system:
        report-system.scm
    gnucash/src/report/utility-reports:
        utility-reports.scm