MIPS: Loongson 2F: Cleanup the #if clauses

This patch adds two new kernel options: CPU_SUPPORTS_CPUFREQ and
CPU_SUPPORTS_ADDRWINCFG to describe the new features of Loongons 2F and
replaces the several ugly #if clauses by them.

These two options will be utilized by the future loongson revisions and
related drivers such as the coming Loongson 2F CPUFreq driver.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/loongson/common/pci.c b/arch/mips/loongson/common/pci.c
index eac43b8..31d8c5e 100644
--- a/arch/mips/loongson/common/pci.c
+++ b/arch/mips/loongson/common/pci.c
@@ -68,7 +68,7 @@
 	deassert for some broken device */
 	LOONGSON_PXARB_CFG = 0x00fe0105ul;
 
-#if defined(CONFIG_CPU_LOONGSON2F) && defined(CONFIG_64BIT)
+#ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
 	/*
 	 * set cpu addr window2 to map CPU address space to PCI address space
 	 */