abootimg: new package

abootimg: new package

This tool might be useful on Android devices modded with Buildroot. Indeed
it allows to modify Android Boot Image partition directly from running
rootfs and so let the user free to keep Android stuff on his device
(mainly bootloader) while testing/using Buildroot kernel/rootfs.

For example, one can modify kernel cmdline on Boot Image partition and
tell Android bootloader to launch kernel with a given rootfs fitted with BR
instead of Android's one.

Build-tested with ./utils/test-pkg -p abootimg -c config.abootimg -a
with config.abootimg containing:
BR2_USE_MMU=y
BR2_PACKAGE_ABOOTIMG=y
BR2_PACKAGE_UTIL_LINUX=y
BR2_PACKAGE_UTIL_LINUX_LIBBLKID=y

                armv5-ctng-linux-gnueabi [ 1/47]: OK
              armv7-ctng-linux-gnueabihf [ 2/47]: OK
                        br-aarch64-glibc [ 3/47]: OK
                           br-arcle-hs38 [ 4/47]: OK
                            br-arm-basic [ 5/47]: OK
                  br-arm-cortex-a9-glibc [ 6/47]: OK
                   br-arm-cortex-a9-musl [ 7/47]: OK
                   br-arm-cortex-m4-full [ 8/47]: SKIPPED
                             br-arm-full [ 9/47]: OK
                    br-arm-full-nothread [10/47]: OK
                      br-arm-full-static [11/47]: OK
                            br-bfin-full [12/47]: SKIPPED
                   br-i386-pentium4-full [13/47]: OK
                br-i386-pentium-mmx-musl [14/47]: OK
                       br-m68k-5208-full [15/47]: SKIPPED
                      br-m68k-68040-full [16/47]: OK
                    br-microblazeel-full [17/47]: OK
                 br-mips32r6-el-hf-glibc [18/47]: OK
                      br-mips64-n64-full [19/47]: OK
                 br-mips64r6-el-hf-glibc [20/47]: OK
                      br-mipsel-o32-full [21/47]: OK
                          br-nios2-glibc [22/47]: OK
                      br-openrisc-uclibc [23/47]: OK
               br-powerpc-603e-basic-cpp [24/47]: OK
             br-powerpc64le-power8-glibc [25/47]: OK
               br-powerpc64-power7-glibc [26/47]: OK
                  br-powerpc-e500mc-full [27/47]: OK
                             br-sh4-full [28/47]: OK
                        br-sparc64-glibc [29/47]: OK
                         br-sparc-uclibc [30/47]: OK
                    br-x86-64-core2-full [31/47]: OK
                          br-x86-64-musl [32/47]: OK
                          br-xtensa-full [33/47]: OK
                     i686-ctng-linux-gnu [34/47]: OK
                          linaro-aarch64 [35/47]: OK
                              linaro-arm [36/47]: OK
             mips64el-ctng_n32-linux-gnu [37/47]: OK
             mips64el-ctng_n64-linux-gnu [38/47]: OK
        powerpc-ctng_e500v2-linux-gnuspe [39/47]: OK
                     sourcery-arm-armv4t [40/47]: OK
                            sourcery-arm [41/47]: OK
                     sourcery-arm-thumb2 [42/47]: OK
                         sourcery-mips64 [43/47]: OK
                           sourcery-mips [44/47]: OK
                          sourcery-nios2 [45/47]: OK
                         sourcery-x86-64 [46/47]: OK
           x86_64-ctng_locales-linux-gnu [47/47]: OK
47 builds, 3 skipped, 0 build failed, 0 legal-info failed

Signed-off-by: Julien BOIBESSOT <julien.boibessot@armadeus.com>
[Thomas: fix license.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>