MIPS: c-r4k: Always install dma flush functions

As nowadays DMA coherence is managed per device, it is possible
to have a system that is defaulted to coherent dma but still
have noncoherent device that needs to use those flush functions.

Just install them unconditionally.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/mm/c-r4k.c

@@ -1867,15 +1867,9 @@ void r4k_cache_init(void)
 	__local_flush_icache_user_range	= local_r4k_flush_icache_user_range;
 
 #ifdef CONFIG_DMA_NONCOHERENT
-	if (dma_default_coherent) {
-		_dma_cache_wback_inv	= (void *)cache_noop;
-		_dma_cache_wback	= (void *)cache_noop;
-		_dma_cache_inv		= (void *)cache_noop;
-	} else {
 	_dma_cache_wback_inv	= r4k_dma_cache_wback_inv;
 	_dma_cache_wback	= r4k_dma_cache_wback_inv;
 	_dma_cache_inv		= r4k_dma_cache_inv;
-	}
 #endif /* CONFIG_DMA_NONCOHERENT */
 
 	build_clear_page();