cc/gcc: remove 'sub-level' version form symbols

Now we use defconfig files to store the samples, we have to be a bit more
conservatives in the symbols names, so as to avoid gigantic version bumps
when updating sub-level versions from a package.

For example (using fictitious versions):
- in crosstool-NG 1.17.0, we choose:
- latest gcc is gcc-linaro-4.7-2012.10, which is the default for the
choice in the menuconfig
- gcc-linaro-4.6-2012.10 is selected
- so, sample has an explicit symbol for the selected gcc version, as it
is not the default
- we update to crosstool-NG 1.18.0:
- latest gcc version is gcc-linaro-4.7-2013.01
- gcc-linaro-46 has been updated to gcc-linaro-4.6-2013.01
- as the sample now has no *valid* symbol to set the gcc version, the
default is used, while we would have expected to still use the 4.6
release from linaro, not the 4.7

Get rid of sub-level (ie. the third digit sequence in versions) from the
symbols for linaro versions.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

# D.U.M.A. - Detect Unintended Memory Access - Memory checker

## depends on ! BACKEND

## help D.U.M.A. - Detect Unintended Memory Access

## help A memory bound checker, with additional features.

## help Formerly known as Electric Fence.

config DUMA_A

    bool

    prompt "Build a static library"

    default y

config DUMA_SO

    bool

    prompt "Build a shared library"

    default y if SHARED_LIBS

choice

    bool

    prompt "D.U.M.A. version"

# Don't remove next line

# CT_INSERT_VERSION_BELOW

config DUMA_V_2_5_15

    bool

    prompt "2_5_15"

endchoice

config DUMA_VERSION

    string

# Don't remove next line

# CT_INSERT_VERSION_STRING_BELOW

    default "2_5_15" if DUMA_V_2_5_15