Revert "xrCore/xr_resource.h: move semantic support" (fixes #1804)

This reverts commit 3882c5c.

Author: Xottab-DUTY

src/xrCore/xr_resource.h

@@ -80,11 +80,6 @@ class resptr_base
         T* prhs = rhs._get();
         _set(prhs);
     }
-    ICF void _set(resptr_base<T>&& rhs)
-    {
-        p_ = rhs.p_;
-        rhs.p_ = nullptr;
-    }
     ICF T* _get() const { return p_; }
     void _clear() { p_ = 0; }
 };
@@ -111,23 +106,13 @@ class resptr_core : public C
         C::p_ = rhs.p_;
         C::_inc();
     }
-    resptr_core(self&& rhs) noexcept
-    {
-        C::p_ = rhs.p_;
-        rhs.p_ = nullptr;
-    }
     ~resptr_core() { C::_dec(); }
     // assignment
     self& operator=(const self& rhs)
     {
         this->_set(rhs);
         return (self&)*this;
     }
-    self& operator=(self&& rhs) noexcept
-    {
-        this->_set(std::move(rhs));
-        return (self&)*this;
-    }
 
     // accessors
     T& operator*() const { return *C::p_; }