The syntax of the linear clause that specifies its argument and
linear-modifier as linear-modifier(list) was deprecated since OpenMP 5.2
and the step modifier was added for specifying the linear step.
Reference: OpenMP 5.2 Spec, Page 627, Line 15
This patch gives basic parsing and semantic support for
"masked taskloop simd" construct introduced in OpenMP 5.1 (section 2.16.8)
Differential Revision: https://reviews.llvm.org/D128693