Move __aeabi_ which are not in libgcc.a to LIBC

The following arm symbols should be exported by libc.so:
    __aeabi_atexit; # arm
    __aeabi_memclr; # arm
    __aeabi_memclr4; # arm
    __aeabi_memclr8; # arm
    __aeabi_memcpy; # arm
    __aeabi_memcpy4; # arm
    __aeabi_memcpy8; # arm
    __aeabi_memmove; # arm
    __aeabi_memmove4; # arm
    __aeabi_memmove8; # arm
    __aeabi_memset; # arm
    __aeabi_memset4; # arm
    __aeabi_memset8; # arm

Bug: https://github.com/android-ndk/ndk/issues/1
Change-Id: I542d1ad023b8aece5dc05a28a9ca549cb51455b4