libc/uClibc: add additional debug level between "minimal" and "all"

During application development it is desirable to enable malloc
debugging and LD_DEBUG support, but the extensive debug spew from
SUPPORT_LD_DEBUG_EARLY is only useful when working on
uClibc's ld.so.

Signed-off-by: Johannes Stezenbach <js@sig21.net>

# Compute Alpha-specific values

CT_DoArchTupleValues () {

    # The architecture part of the tuple:

    CT_TARGET_ARCH="${CT_ARCH}${CT_ARCH_ALPHA_VARIANT}"

}