[CMake] Add first CMake cache files

Summary:
CMake cache scripts pre-populate the CMakeCache in a build directory with commonly used settings.
The CMake invocation from D61952 could look like this:

```
cmake -G Ninja -C /path/to/llvm-project/lldb/cmake/caches/Apple-lldb-osx.cmake -DLLVM_ENABLE_PROJECTS="clang;libcxx;libcxxabi;lldb" ../llvm-project/llvm
```

Options specified on the command line will override options in the cache files (as long as caches don't use `FORCE`).
What do you think? (This is a first proposal and not set in stone.)

Reviewers: xiaobai, compnerd, JDevlieghere, aprantl, labath

Subscribers: mgorny, lldb-commits, #lldb

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D61956

llvm-svn: 361069

lldb/cmake/caches/Apple-lldb-base.cmake

@@ -0,0 +1,8 @@
+set(LLVM_TARGETS_TO_BUILD X86;ARM;AArch64 CACHE STRING "")
+set(LLVM_INSTALL_TOOLCHAIN_ONLY ON CACHE BOOL "")
+
+# Release builds set these explicitly:
+#set(LLDB_VERSION_MAJOR 9999 CACHE STRING "")
+#set(LLDB_VERSION_MINOR 9 CACHE STRING "")
+#set(LLDB_VERSION_PATCH 9 CACHE STRING "")
+#set(LLDB_VERSION_SUFFIX git CACHE STRING "")

lldb/cmake/caches/Apple-lldb-macOS.cmake

@@ -0,0 +1,22 @@
+include(${CMAKE_CURRENT_LIST_DIR}/Apple-lldb-base.cmake)
+
+set(LLDB_BUILD_FRAMEWORK ON CACHE BOOL "")
+set(LLDB_NO_INSTALL_DEFAULT_RPATH ON CACHE BOOL "")
+
+# Set the install prefix to the default install location on the enduser machine.
+# If the location is not writeable on the build machine, specify another prefix
+# in the DESTDIR environment variable, e.g.: DESTDIR=/tmp ninja install
+set(CMAKE_INSTALL_PREFIX /Applications/Xcode.app/Contents/Developer/usr CACHE STRING "")
+
+# Choose the install location for LLDB.framework so that it matches the
+# INSTALL_RPATH of the lldb driver. It's either absolute or relative to
+# CMAKE_INSTALL_PREFIX. In any case, DESTDIR will be an extra prefix.
+set(LLDB_FRAMEWORK_INSTALL_DIR /Applications/Xcode.app/Contents/SharedFrameworks CACHE STRING "")
+
+# Release builds may change these:
+set(CMAKE_OSX_DEPLOYMENT_TARGET 10.11 CACHE STRING "")
+set(LLDB_USE_SYSTEM_DEBUGSERVER ON CACHE BOOL "")
+set(LLVM_EXTERNALIZE_DEBUGINFO OFF CACHE BOOL "")
+
+set(CMAKE_BUILD_TYPE RelWithDebInfo CACHE STRING "")
+set(LLVM_ENABLE_MODULES ON CACHE BOOL "")