MIPS: Don't specify STACKPROTECTOR in defconfigs

Only one defconfig has a STACKPROTECTOR value.  And it asks for
the strong variant, which isn't supported by older toolchains.

Due to the nature of MIPS having more platform specific code than say
x86, the allyesconfig and allmodconfig aren't as effective for build
coverage.  So, in addition, I like to use a trivial script to walk all
the defconfigs and build each one.

However I will get false positives on unsupported stackprotector values
with an older toolchain like gcc-4.6.3.  As in this instance I am just
using the compiler as a glorified syntax checker on a machine where I
build a bunch of other arch for the same reason, there is no real
motivation to get a newer toolchain for improved optimization etc.

Since there is only one of them, and there is nothing about these
settings that are board/platform specific, I propose we just eliminate
the existing instance and take the default.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: James Hartley <james.hartley@imgtec.com>
Cc: Ionela Voinescu <ionela.voinescu@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13846/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/configs/pistachio_defconfig

@@ -29,7 +29,6 @@ CONFIG_CC_OPTIMIZE_FOR_SIZE=y
 CONFIG_EMBEDDED=y
 # CONFIG_COMPAT_BRK is not set
 CONFIG_PROFILING=y
-CONFIG_CC_STACKPROTECTOR_STRONG=y
 CONFIG_MODULES=y
 CONFIG_MODULE_UNLOAD=y
 CONFIG_MODULE_FORCE_UNLOAD=y