Apply clang format to src/variable.cpp
Apply clang format to src/variable.cpp
hsorby/libcellml,hsorby/libcellml,cellml/libcellml,cellml/libcellml,hsorby/libcellml,nickerso/libcellml,nickerso/libcellml,nickerso/libcellml,nickerso/libcellml,cellml/libcellml,hsorby/libcellml,cellml/libcellml