iwlwifi: remove references to unsupported HW

There are still some references to 3945 and 4965 HW, which were never
supported in iwlwifi.  These references were inherited from a previous
project and are irrelevant here.  Additionally, remove some irrelevant
references to 5100 HW.  Remove all these.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

drivers/net/wireless/intel/iwlwifi/pcie/trans.c

@@ -1842,8 +1842,8 @@ static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans,
 	 * These bits say the device is running, and should keep running for
 	 * at least a short while (at least as long as MAC_ACCESS_REQ stays 1),
 	 * but they do not indicate that embedded SRAM is restored yet;
-	 * 3945 and 4965 have volatile SRAM, and must save/restore contents
-	 * to/from host DRAM when sleeping/waking for power-saving.
+	 * HW with volatile SRAM must save/restore contents to/from
+	 * host DRAM when sleeping/waking for power-saving.
 	 * Each direction takes approximately 1/4 millisecond; with this
 	 * overhead, it's a good idea to grab and hold MAC_ACCESS_REQUEST if a
 	 * series of register accesses are expected (e.g. reading Event Log),
@@ -1851,8 +1851,9 @@ static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans,
 	 *
 	 * CSR_UCODE_DRV_GP1 register bit MAC_SLEEP == 0 indicates that
 	 * SRAM is okay/restored.  We don't check that here because this call
-	 * is just for hardware register access; but GP1 MAC_SLEEP check is a
-	 * good idea before accessing 3945/4965 SRAM (e.g. reading Event Log).
+	 * is just for hardware register access; but GP1 MAC_SLEEP
+	 * check is a good idea before accessing the SRAM of HW with
+	 * volatile SRAM (e.g. reading Event Log).
 	 *
 	 * 5000 series and later (including 1000 series) have non-volatile SRAM,
 	 * and do not save/restore SRAM when power cycling.