fix a compile warning in amd76x_pm.c

I got the following compile warning in 2.4.22-pre10:

<-- snip -->

...
gcc -D__KERNEL__ -I/home/bunk/linux/kernel-2.4/linux-2.4.22-pre10-full/include - Wall -Wstrict-prototypes -Wno-trigraphs -O2 -fno-strict-aliasing
-fno-common -pipe -mpreferred-stack-boundary=2 -march=k6 -nostdinc -iwithprefix
include -DKBUILD_BASENAME=amd76x_pm -c -o amd76x_pm.o amd76x_pm.c amd76x_pm.c:483: warning: `activate_amd76x_SLP' defined but not used
...

<-- snip -->

The following patch puts this function under the same #ifdef as it's only caller:

@@ -474,7 +474,7 @@
 }
 #endif
 
-
+#ifdef AMD76X_POS
 /*
  * Activate sleep state via its ACPI register (PM1_CNT).
  */

@@ -489,8 +489,6 @@
 	outw(regshort, amd76x_pm_cfg.slp_reg);
 }
 
-
-#ifdef AMD76X_POS
 /*
  * Wrapper function to activate POS sleep state.
  */

I've tested the compilation with 2.4.22-pre10.

Please apply
Adrian

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed