[PATCH] eal/arm: replace RTE_BUILD_BUG on non-constant

[Wathsala Wathawana Vithanage]

> Subject: [PATCH] eal/arm: replace RTE_BUILD_BUG on non-constant
> 
> The ARM implementation of rte_pause uses RTE_BUILD_BUG_ON to check
> memorder, which is not constant. This causes compile errors when it is
> enabled with RTE_ARM_USE_WFE. eg.

Use of wfe based rte_wait_until_equal_ implementations  had performance issues
when used in lock free data structures like rte_ring. 
To prevent these functions from getting included RTE_ARM_USE_WFE was
introduced some time back and this issue has been hiding so far because of that.
Solution looks good to me.  

> 
> ../lib/eal/arm/include/rte_pause_64.h: In function ‘rte_wait_until_equal_16’:
> ../lib/eal/include/rte_common.h:530:56: error: expression in static assertion
> is not constant
>   530 | #define RTE_BUILD_BUG_ON(condition) do {
> static_assert(!(condition), #condition); } while (0)
>       |                                                        ^~~~~~~~~~~~
> ../lib/eal/arm/include/rte_pause_64.h:156:9: note: in expansion of macro
> ‘RTE_BUILD_BUG_ON’
>   156 |         RTE_BUILD_BUG_ON(memorder != rte_memory_order_acquire &&
>       |         ^~~~~~~~~~~~~~~~
> 
> This has been the case since the switch to C11 assert (537caad2). Fix the
> compile errors by replacing the check with an RTE_ASSERT.
> 
> Signed-off-by: Daniel Gregory <daniel.gregory at bytedance.com>

Acked-by: Wathsala Vithanage <wathsala.vithanage at arm.com>