RHS Compat - Add Mk17 barrel length config entries

[armyinf0703]

Was missing barrel lengths so the LB version was performing the same as the CQC version. Used FNs website for the barrel lengths.

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[Lazejun]

#7702 , there are way more than just the Scars

Also this will not set Values for RHSSAFs Black and Tan Scars.

[PabstMirror]

Looks like this was fully handled by #7702

    class rhs_weap_SCAR_H_Base;
    class rhs_weap_SCAR_H_CQC_Base: rhs_weap_SCAR_H_Base {
        ACE_barrelTwist = 304.8; // 1:12"
        ACE_barrelLength = 330.0;
    };
    class rhs_weap_SCAR_H_LB_Base: rhs_weap_SCAR_H_CQC_Base {
        ACE_barrelTwist = 304.8; // 1:12"
        ACE_barrelLength = 508.0;
    };
    class rhs_weap_SCAR_H_STD_Base: rhs_weap_SCAR_H_LB_Base {
        ACE_barrelTwist = 304.8; // 1:12"
        ACE_barrelLength = 406.0;
    };

[PabstMirror]

done in #7702
https://github.com/acemod/ACE3/blob/master/optionals/compat_rhs_usf3/CfgWeapons.hpp#L129