MIPS: Split I & D cache line size config

Allow L1 Icache & L1 Dcache line size to be specified separately, since
there's no architectural mandate that they be the same. The
[id]cache_line_size functions are tidied up to take advantage of the
fact that the Kconfig entries are always present to simply check them
for zero rather than needing to #ifdef on their presence.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
[removed CONFIG_SYS_CACHELINE_SIZE in include/configs/pic32mzdask.h]
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/arch/mips/include/asm/cache.h b/arch/mips/include/asm/cache.h
index 806bd26..0cea581 100644
--- a/arch/mips/include/asm/cache.h
+++ b/arch/mips/include/asm/cache.h
@@ -12,4 +12,11 @@
 
 #define ARCH_DMA_MINALIGN	(L1_CACHE_BYTES)
 
+/*
+ * CONFIG_SYS_CACHELINE_SIZE is still used in various drivers primarily for
+ * DMA buffer alignment. Satisfy those drivers by providing it as a synonym
+ * of ARCH_DMA_MINALIGN for now.
+ */
+#define CONFIG_SYS_CACHELINE_SIZE ARCH_DMA_MINALIGN
+
 #endif /* __MIPS_CACHE_H__ */