libc/glibc: spelling fixes in the menuconfig help entries

nits:
- fix the spelling of changing.
- 'chose' is the correct past tense.

Signed-off-by: Michael Hope <michael.hope@linaro.org>

# Compute sparc-specific values

CT_DoArchTupleValues() {

    # That's the only thing to override

    if [ "${CT_ARCH_64}" = "y" ]; then

        CT_TARGET_ARCH="${CT_ARCH}64"

    fi

}