[LLDB] Fix whitespace/tabs mismatch in lldbsuite Makefile.rules

This patch fixes whitespace/tabs mismatch in
lldb/packages/Python/lldbsuite/test/make/Makefile.rules

Legacy make files always used tabs though modern make version can
work with white-spaces I have chosen the legacy just to be safe.

Signed-off-by: Muhammad Omair Javaid <omair.javaid@linaro.org>

Differential Revision: https://reviews.llvm.org/D70154