Build: Switch to CMake :^)

Closes https://github.com/SerenityOS/serenity/issues/2080

Libraries/LibC/CMakeLists.txt

@@ -0,0 +1,65 @@
+set(LIBC_SOURCES
+    arpa/inet.cpp
+    assert.cpp
+    crt0.cpp
+    ctype.cpp
+    cxxabi.cpp
+    dirent.cpp
+    dlfcn.cpp
+    fcntl.cpp
+    getopt.cpp
+    grp.cpp
+    ioctl.cpp
+    libcinit.cpp
+    libgen.cpp
+    locale.cpp
+    malloc.cpp
+    mman.cpp
+    mntent.cpp
+    netdb.cpp
+    poll.cpp
+    pwd.cpp
+    qsort.cpp
+    scanf.cpp
+    sched.cpp
+    serenity.cpp
+    setjmp.S
+    signal.cpp
+    stat.cpp
+    stdio.cpp
+    stdlib.cpp
+    string.cpp
+    strings.cpp
+    syslog.cpp
+    sys/ptrace.cpp
+    sys/select.cpp
+    sys/socket.cpp
+    sys/uio.cpp
+    sys/wait.cpp
+    termcap.cpp
+    termios.cpp
+    time.cpp
+    times.cpp
+    ulimit.cpp
+    unistd.cpp
+    utime.cpp
+    utsname.cpp
+    wchar.cpp
+)
+
+file(GLOB AK_SOURCES "../../AK/*.cpp")
+file(GLOB ELF_SOURCES "../LibELF/*.cpp")
+set(ELF_SOURCES ${ELF_SOURCES} ../LibELF/Arch/i386/plt_trampoline.S)
+
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DSERENITY_LIBC_BUILD")
+
+add_library(crt0 STATIC crt0.cpp)
+add_custom_command(
+    TARGET crt0
+    COMMAND install -D $<TARGET_OBJECTS:crt0> ${CMAKE_INSTALL_PREFIX}/usr/lib/crt0.o
+)
+
+set(SOURCES ${LIBC_SOURCES} ${AK_SOURCES} ${ELF_SOURCES})
+serenity_libc(LibC c)
+target_link_libraries(LibC crt0)
+add_dependencies(LibC LibM)