Since the recent bump of Bootlin toolchains in947dbc92a2("toolchain/toolchain-external/toolchain-external-bootlin: update to Bootlin toolchains 2025.08-1"), our grub2 tests are failing as the new uClibc toolchains based on gcc 14.x have an issue building grub. Until this issue gets fixed at the uClibc level and since anyway glibc is now the default in Buildroot, let's switch to using glibc toolchains. Fixes: https://gitlab.com/buildroot.org/buildroot/-/jobs/10972858692 https://gitlab.com/buildroot.org/buildroot/-/jobs/10972858686 https://gitlab.com/buildroot.org/buildroot/-/jobs/10972858680 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Julien Olivain <ju.o@free.fr> (cherry picked from commitf4d01d1c5e) Signed-off-by: Thomas Perale <thomas.perale@mind.be>