doc: Add old toolchain pages to redirects

The toolchain pages have been living in develop/ for a while now.

Signed-off-by: Benjamin Cabé <[email protected]>

Author: kartben

doc/_scripts/redirects.py

@@ -19,6 +19,9 @@
     ('development_process/issues', 'project/issues'),
     ('development_process/proposals', 'project/proposals'),
     ('getting_started/index', 'develop/getting_started/index'),
+    ('getting_started/toolchain_3rd_party_x_compilers', 'develop/toolchains/index'),
+    ('getting_started/toolchain_custom_cmake', 'develop/toolchains/custom_cmake'),
+    ('getting_started/toolchain_other_x_compilers', 'develop/toolchains/other_x_compilers'),
     ('guides/arch/arm_cortex_m', 'hardware/arch/arm_cortex_m'),
     ('guides/arch/index', 'hardware/arch/index'),
     ('guides/arch/x86', 'hardware/arch/x86'),