Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
diff --git a/drivers/ssb/pci.c b/drivers/ssb/pci.c
index a467b20..6f34963 100644
--- a/drivers/ssb/pci.c
+++ b/drivers/ssb/pci.c
@@ -670,7 +670,7 @@
 		ssb_printk(KERN_ERR PFX "No SPROM available!\n");
 		return -ENODEV;
 	}
-	if (bus->chipco.dev) {	/* can be unavailible! */
+	if (bus->chipco.dev) {	/* can be unavailable! */
 		/*
 		 * get SPROM offset: SSB_SPROM_BASE1 except for
 		 * chipcommon rev >= 31 or chip ID is 0x4312 and