[lldb] Fix lldb build on musl
[lldb] Fix lldb build on musl

Summary: limits.h is needed for getting PATH_MAX definition, this comes to fore
with musl libc where limits.h is not included indirectly via other system headers.

Patch by Khem Raj, thanks!

Reviewers: compnerd

Reviewed By: compnerd

Subscribers: llvm-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D31275

git-svn-id: 4c4cc70b1ef44ba2b7963015e681894188cea27e@340876 91177308-0d34-0410-b5e6-96231b3b80d8
(cherry picked from commit dbd0a0cf42aef7edd3385cda9240ba342a1aaadc)

apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb