Revert "Try to remove -lunwind from link flags"

This reverts commit 0a4a0e1.

Author: chestnykh

libunwind/test/configs/llvm-libunwind-shared.cfg.in

@@ -23,10 +23,6 @@ if '@CMAKE_DL_LIBS@':
 # Stack unwinding tests need unwinding tables and these are not generated by default on all targets.
 compile_flags.append('-funwind-tables')
 
-# Use libunwind from llvm
-compile_flags.append('-rtlib=compiler-rt')
-compile_flags.append('-unwindlib=libunwind')
-
 local_sysroot = '@CMAKE_OSX_SYSROOT@' or '@CMAKE_SYSROOT@'
 config.substitutions.append(('%{flags}',
     '-isysroot {}'.format(local_sysroot) if local_sysroot else ''
@@ -35,7 +31,7 @@ config.substitutions.append(('%{compile_flags}',
     '-nostdinc++ -I %{{include}} {}'.format(' '.join(compile_flags))
 ))
 config.substitutions.append(('%{link_flags}',
-    '-L %{{lib}} -Wl,-rpath,%{{lib}} {}'.format(' '.join(link_flags))
+    '-L %{{lib}} -Wl,-rpath,%{{lib}} -lunwind {}'.format(' '.join(link_flags))
 ))
 config.substitutions.append(('%{exec}',
     '%{executor} --execdir %T -- '