sphinx-lint: role missing opening tag colon

Fix all instances missing-space-before-role as reported by 'make sphinx-lint'.

(From yocto-docs rev: 255bfc8c195bbc84a78a4985cf2775c87e525794)

Signed-off-by: Trevor Woerner <twoerner@gmail.com>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>

documentation/ref-manual/variables.rst

@@ -8909,7 +8909,7 @@ system and gives an overview of their function and contents.
       :doc:`/sdk-manual/index` manual.
 
       Note that this variable applies to building an SDK, not an eSDK,
-      in which case the term:`TOOLCHAIN_HOST_TASK_ESDK` setting should be
+      in which case the :term:`TOOLCHAIN_HOST_TASK_ESDK` setting should be
       used instead.
 
    :term:`TOOLCHAIN_HOST_TASK_ESDK`