message: simplify cmake file, rename library name
diff: project(librs C)
  -if(EXISTS "${CMAKE_SOURCE_DIR}/.git")
  - find_package(Git)
  - if(GIT_FOUND)
  - execute_process(
  - COMMAND "${GIT_EXECUTABLE}" rev-parse HEAD
  - WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
  - OUTPUT_VARIABLE GIT_COMMIT_HASH
  - RESULT_VARIABLE GIT_CALL_RESULT
  - OUTPUT_STRIP_TRAILING_WHITESPACE
  - )
  - if(GIT_CALL_RESULT EQUAL 0)
  - set(COMMIT_HASH "${GIT_COMMIT_HASH}")
  - endif()
  - endif()
  -endif()
  -
  # Add the Cargo project to build the Rust library.
  -set(HERMIT_RS "${CMAKE_BINARY_DIR}/hermit_rs/${HERMIT_ARCH}-unknown-hermit-kernel/${CARGO_BUILDTYPE_OUTPUT}/libhermit_rs.a")
  +set(HERMIT_RS "${CMAKE_BINARY_DIR}/hermit_rs/${HERMIT_ARCH}-unknown-hermit-kernel/${CARGO_BUILDTYPE_OUTPUT}/libhermit.a")
  add_custom_target(hermit_rs
  COMMAND
  ${CMAKE_COMMAND} -E env CARGO_TARGET_DIR=${CMAKE_BINARY_DIR}/hermit_rs RUST_TARGET_PATH=${HERMIT_ROOT}/librs
  @@ -50,30 +34,10 @@ set_target_properties(hermit-bootstrap PROPERTIES ARCHIVE_OUTPUT_NAME hermit)
  add_custom_command(
  TARGET hermit-bootstrap POST_BUILD
  - # Merge the Rust library into this static library.
  - COMMAND
  - ${CMAKE_AR} x ${HERMIT_RS}
  - COMMAND
  - ${CMAKE_AR} rcs $<TARGET_FILE:hermit-bootstrap> *.o
  - COMMAND
  - ${CMAKE_COMMAND} -E remove *.o
  -
  # Convert the combined library to osabi "Standalone"
  COMMAND
  ${CMAKE_ELFEDIT} --output-osabi Standalone $<TARGET_FILE:hermit-bootstrap>
  - # Redefine some reserved Rust symbols to avoid collisions with similarly named symbols from Rust application code.
  - # Note that some of them only appear in Debug builds of HermitCore!
  - COMMAND
  - ${CMAKE_OBJCOPY}
  - --redefine-sym rust_begin_unwind=HermitCore_Kernel_rust_begin_unwind
  - --redefine-sym rust_oom=HermitCore_Kernel_rust_oom
  - --redefine-sym __rust_alloc=HermitCore_Kernel___rust_alloc
  - --redefine-sym __rust_alloc_zeroed=HermitCore_Kernel___rust_alloc_zeroed
  - --redefine-sym __rust_dealloc=HermitCore_Kernel___rust_dealloc
  - --redefine-sym __rust_realloc=HermitCore_Kernel___rust_realloc
  - $<TARGET_FILE:hermit-bootstrap>
  -
  # Copy libhermit.a into local prefix directory so that all subsequent
  # targets can link against the freshly built version (as opposed to
  # linking against the one supplied by the toolchain)
  