cc: add options to differentiate the need for pass-1 and pass-2

In some cases, building the core pass-1 is unneeded, as the C library
will not try to build anything when installing headers, or sill not
install anything at all.

This is for example the case for newlib, wihch does not require a core
pass-1 since it builds nothing and installs no header.

This should also be the case for newer glibc-es with newer gcc-es,
which no longer require a core pass-1, since the circular dependency
glibc <-> gcc (about TLS?) has been resolved.

Reported-by: Trevor Woerner <trevor.woerner@linaro.org>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

CT_EXPERIMENTAL=y

CT_LOCAL_TARBALLS_DIR="${HOME}/src"

CT_SAVE_TARBALLS=y

CT_LOG_EXTRA=y

CT_ARCH_ARCH="4kc"

CT_ARCH_TUNE="4kc"

CT_ARCH_FLOAT_SW=y

CT_ARCH_mips=y

CT_TARGET_VENDOR="ar2315"

CT_KERNEL_linux=y

CT_KERNEL_V_2_6_33=y

CT_BINUTILS_V_2_19_1a=y

CT_CC_V_4_3_2=y

CT_CC_LANG_CXX=y

CT_LIBC_EGLIBC_V_2_9=y

CT_EGLIBC_REVISION="{2009-07-21}"

# CT_LIBC_GLIBC_FORCE_UNWIND is not set

CT_LIBC_GLIBC_KERNEL_VERSION_CHOSEN=y

CT_LIBC_GLIBC_MIN_KERNEL_VERSION="2.6.25"

CT_DEBUG_dmalloc=y

CT_DEBUG_gdb=y

CT_GDB_V_6_8a=y

CT_DEBUG_strace=y

CT_STRACE_V_4_5_19=y

CT_GMP_V_4_3_2=y

CT_MPFR_V_2_4_2=y