Introduce the variable BR2_TOOLCHAIN_HAS_UCONTEXT

It is set when the platform exposes the struct ucontext_t.

This avoids duplication of logic inside each package requiring
the use of that type.

Signed-off-by: Patrick Havelange <patrick.havelange@essensium.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2 files changed