Aligning rntm_t struct to 64 byte address to address performance issues.

Non aligned rntm_t struct can potentially have its first/last cache
line shared with other objects in memory. This could affect performance
depending on how much the shared cache lines are used. rntm_t struct is
aligned to 64 bytes to workaround this issue.

Change-Id: Id0956fca771be062ada9f81e8cd75ac1f290fd8e

frame/include/bli_type_defs.h

@@ -1586,7 +1586,7 @@ typedef struct cntx_s
 // NOTE: The order of these fields must be kept consistent with the definition
 // of the BLIS_RNTM_INITIALIZER macro in bli_rntm.h.
 
-typedef struct rntm_s
+typedef struct __attribute__((aligned(64))) rntm_s
 {
 	// "External" fields: these may be queried by the end-user.
 	bool      auto_factor;