qla2x00t-32gbit: Use 64-bit max LUNs when supported

The Linux 3.10 backport selected uint unconditionally for ql2xmaxlun,
limiting the module parameter to 32 bits even on current kernels.

Select uint only when param_check_ullong is absent from the kernel's
module parameter API. Otherwise retain the upstream uint64_t/ullong type.
Use the same feature check for the extern declaration so all driver
translation units agree, including vendor kernels with this API backported.

The default value and existing 16-bit limit for older HBAs are unchanged.

qla2x00t-32gbit/qla_gbl.h

@@ -176,7 +176,7 @@ extern int ql2xgffidenable;
 extern int ql2xenabledif;
 extern int ql2xenablehba_err_chk;
 extern int ql2xdontresethba;
-#if 1
+#ifndef param_check_ullong
 extern uint ql2xmaxlun;
 #else
 extern uint64_t ql2xmaxlun;

qla2x00t-32gbit/qla_os.c

@@ -243,7 +243,8 @@ MODULE_PARM_DESC(ql2xdontresethba,
 		" 0 (Default) -- Reset on failure.\n"
 		" 1 -- Do not reset on failure.\n");
 
-#if 1
+/* Older kernels may lack the ullong module parameter type. */
+#ifndef param_check_ullong
 uint ql2xmaxlun = MAX_LUNS;
 module_param(ql2xmaxlun, uint, S_IRUGO);
 #else