[2.6.25 patch] mips: fix SNI_RM EISA=n compilation

[Adrian Bunk <bunk@kernel.org>]

This patch fixes the following build error with CONFIG_EISA=n caused by 
commit 231a35d37293ab88d325a9cb94e5474c156282c0:

<--  snip -->

...
  LD      .tmp_vmlinux1
arch/mips/sni/built-in.o: In function `snirm_a20r_setup_devinit':
a20r.c:(.init.text+0x42c): undefined reference to `sni_eisa_root_init'
a20r.c:(.init.text+0x42c): relocation truncated to fit: R_MIPS_26 against `sni_eisa_root_init'
arch/mips/sni/built-in.o: In function `snirm_setup_devinit':
rm200.c:(.init.text+0x52c): undefined reference to `sni_eisa_root_init'
rm200.c:(.init.text+0x52c): relocation truncated to fit: R_MIPS_26 against `sni_eisa_root_init'
make[1]: *** [.tmp_vmlinux1] Error 1

<--  snip  -->

Signed-off-by: Adrian Bunk <bunk@kernel.org>

---
f6a6c34454cbe463e2d8d567d9e0659161a82a72 diff --git a/include/asm-mips/sni.h b/include/asm-mips/sni.h
index e716447..8c1eb02 100644
--- a/include/asm-mips/sni.h
+++ b/include/asm-mips/sni.h
@@ -228,7 +228,14 @@ extern void sni_pcimt_irq_init(void);
 extern void sni_cpu_time_init(void);
 
 /* eisa init for RM200/400 */
+#ifdef CONFIG_EISA
 extern int sni_eisa_root_init(void);
+#else
+static inline int sni_eisa_root_init(void)
+{
+	return 0;
+}
+#endif
 
 /* common irq stuff */
 extern void (*sni_hwint)(void);