C++11: Use member declaration initalizations. No functional change intended.

src/V3WidthSel.cpp

@@ -64,9 +64,9 @@ private:
         AstNodeDType* m_dtypep;  // Data type for the 'from' slice
         VNumRange m_fromRange;  // Numeric range bounds for the 'from' slice
         FromData(AstNodeDType* errp, AstNodeDType* dtypep, const VNumRange& fromRange)
-            : m_errp(errp)
-            , m_dtypep(dtypep)
-            , m_fromRange(fromRange) {}
+            : m_errp{errp}
+            , m_dtypep{dtypep}
+            , m_fromRange{fromRange} {}
         ~FromData() {}
     };
     FromData fromDataForArray(AstNode* nodep, AstNode* basefromp) {