libkldelf: use warnx instead of printf

Sponsored by:	Juniper Networks, Inc.
Reviewed by:	markj
Differential Revision:	https://reviews.freebsd.org/D46893

lib/libkldelf/ef_obj.c

@@ -345,20 +345,20 @@ ef_obj_open(struct elf_file *efile, int verbose)
 	if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
 	    (ef->nrel != 0 && ef->reltab == NULL) ||
 	    (ef->nrela != 0 && ef->relatab == NULL)) {
-		printf("malloc failed\n");
+		warnx("malloc failed");
 		error = ENOMEM;
 		goto out;
 	}
 
 	if (elf_read_symbols(efile, symtabindex, &ef->ddbsymcnt,
 	    &ef->ddbsymtab) != 0) {
-		printf("elf_read_symbols failed\n");
+		warnx("elf_read_symbols failed");
 		goto out;
 	}
 
 	if (elf_read_string_table(efile, &shdr[symstrindex], &ef->ddbstrcnt,
 	    &ef->ddbstrtab) != 0) {
-		printf("elf_read_string_table failed\n");
+		warnx("elf_read_string_table failed");
 		goto out;
 	}
 
@@ -367,7 +367,7 @@ ef_obj_open(struct elf_file *efile, int verbose)
 	    shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
 		if (elf_read_string_table(efile, &shdr[hdr->e_shstrndx],
 		    &ef->shstrcnt, &ef->shstrtab) != 0) {
-			printf("elf_read_string_table failed\n");
+			warnx("elf_read_string_table failed");
 			goto out;
 		}
 	}
@@ -413,7 +413,7 @@ ef_obj_open(struct elf_file *efile, int verbose)
 			ef->reltab[rl].sec = shdr[i].sh_info;
 			if (elf_read_rel(efile, i, &ef->reltab[rl].nrel,
 			    &ef->reltab[rl].rel) != 0) {
-				printf("elf_read_rel failed\n");
+				warnx("elf_read_rel failed");
 				goto out;
 			}
 			rl++;
@@ -422,7 +422,7 @@ ef_obj_open(struct elf_file *efile, int verbose)
 			ef->relatab[ra].sec = shdr[i].sh_info;
 			if (elf_read_rela(efile, i, &ef->relatab[ra].nrela,
 			    &ef->relatab[ra].rela) != 0) {
-				printf("elf_read_rela failed\n");
+				warnx("elf_read_rela failed");
 				goto out;
 			}
 			ra++;