[mips] Removed the remainder of MipsCC. NFC.

Summary:
One of the calls to AllocateStack (the one in LowerCall) doesn't look like
it should be there but it was there before and removing it breaks the
frame size calculation.

Reviewers: vmedic, theraven

Reviewed By: theraven

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D6116

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221529 91177308-0d34-0410-b5e6-96231b3b80d8
Pass PRIVATE to target_link_libraries if using shared libraries.

A shared library (unlike a .a), has its dependencies recorded in the library and
we can pass PRIVATE to target_link_libraries.

This patch then removes some bogus dependencies when using
BUILD_SHARED_LIBS=ON. For example, we go from

build lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/AggressiveAntiDepBreaker.cpp.o:
CXX_COMPILER /home/espindola/llvm/llvm/lib/CodeGen/AggressiveAntiDepBreaker.cpp
|| include/llvm/IR/intrinsics_gen lib/libLLVMSupport.so
lib/libLLVMCore.so lib/libLLVMBitReader.so
lib/libLLVMTransformUtils.so lib/libLLVMInstCombine.so
lib/libLLVMScalarOpts.so lib/libLLVMipa.so lib/libLLVMAnalysis.so
lib/libLLVMMCParser.so lib/libLLVMMC.so lib/libLLVMObject.so
lib/libLLVMTarget.so lib/libLLVMProfileData.so

to

build lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/AggressiveAntiDepBreaker.cpp.o:
CXX_COMPILER /home/espindola/llvm/llvm/lib/CodeGen/AggressiveAntiDepBreaker.cpp
|| include/llvm/IR/intrinsics_gen lib/libLLVMSupport.so
lib/libLLVMCore.so lib/libLLVMTransformUtils.so
lib/libLLVMScalarOpts.so lib/libLLVMAnalysis.so lib/libLLVMMC.so
lib/libLLVMTarget.so

In fact, build.ninja goes from 5231028 bytes to 4896759 bytes.

With this, old verisons of bfd ld (2.24 is OK, 2.23 warns) will print a bogus
warning when building with BUILD_SHARED_LIBS.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221530 91177308-0d34-0410-b5e6-96231b3b80d8
[CMake] LLVMSupport: Give system_libs PRIVATE scope when LLVMSupport is built as SHARED. Users of LLVMSupport won't inherit ${system_libs}.

unittests/SupporTests is another user of libpthreads. Apply LLVM_SYSTEM_LIBS for him explicitly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221531 91177308-0d34-0410-b5e6-96231b3b80d8