rcu-tasks: Always inline rcu_irq_work_resched()

Thanks to CONFIG_DEBUG_SECTION_MISMATCH, empty functions can be
generated out of line.  rcu_irq_work_resched() can be called from
noinstr code, so make sure it's always inlined.

Fixes: 56450649 ("rcu/context-tracking: Move deferred nocb resched to context tracking")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/e84f15f013c07e4c410d972e75620c53b62c1b3e.1743481539.git.jpoimboe@kernel.org
Closes: https://lore.kernel.org/d1eca076-fdde-484a-b33e-70e0d167c36d@infradead.org