Make setting of cma_pernuma tech preview

JIRA: https://issues.redhat.com/browse/RHEL-59621
Upstream status: RHEL-only

CONFIG_DMA_NUMA_CMA will be set for some architectures shortly. Since this
enablement is new for RHEL, mark it tech preview and taint the kernel if the
feature is enabled on the kernel command line.

Signed-off-by: Chris von Recklinghausen <crecklin@redhat.com>

Author: Chris von Recklinghausen

kernel/dma/contiguous.c

@@ -159,6 +159,7 @@ static inline __maybe_unused phys_addr_t cma_early_percent_memory(void)
 static void __init dma_numa_cma_reserve(void)
 {
 	int nid;
+	unsigned int tech_preview = 0;
 
 	for_each_node(nid) {
 		int ret;
@@ -180,6 +181,7 @@ static void __init dma_numa_cma_reserve(void)
 			if (ret)
 				pr_warn("%s: reservation failed: err %d, node %d", __func__,
 					ret, nid);
+			tech_preview += 1;
 		}
 
 		if (numa_cma_size[nid]) {
@@ -191,8 +193,11 @@ static void __init dma_numa_cma_reserve(void)
 			if (ret)
 				pr_warn("%s: reservation failed: err %d, node %d", __func__,
 					ret, nid);
+			tech_preview += 1;
 		}
 	}
+	if (tech_preview)
+		mark_tech_preview("dma-numa-cma-reserve", NULL);
 }
 #else
 static inline void __init dma_numa_cma_reserve(void)