Update swtpm to version 0.7.3 / rev 12 via SR 974426
    
    https://build.opensuse.org/request/show/974426
    by user msmeissn + dimstar_suse
    - Updated to version 0.7.3:
      - swtpm:
        - Use uint64_t in tlv_data_append() to avoid integer overflows
        - Use uint64_t to avoid integer wrap-around when adding a uint32_t
    - removed allow-FORTIFY_SOURCE=3.patch (upstreamed) (forwarded request 973850 from msmeissn)