r246916 probably broke amd64 build

[Simon L. B. Nielsen]

Hey,

I think r246916 broke the build. I get the following when building amd64 kernel:

cc -c -O2 -frename-registers -pipe -fno-strict-aliasing  -std=c99 -g
-Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes
-Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual  -Wundef
-Wno-pointer-sign -fformat-extensions  -Wmissing-include-dirs
-fdiagnostics-show-option   -nostdinc  -I. -I/usr/src/sys
-I/usr/src/sys/contrib/altq -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS
-include opt_global.h -fno-common -finline-limit=8000 --param
inline-unit-growth=100 --param large-function-growth=1000
-fno-omit-frame-pointer -mcmodel=kernel -mno-red-zone -mno-mmx
-mno-sse -msoft-float  -fno-asynchronous-unwind-tables -ffreestanding
-fstack-protector -Werror  /usr/src/sys/x86/isa/clock.c
cc1: warnings being treated as errors
/usr/src/sys/x86/isa/clock.c: In function 'set_i8254_freq':
/usr/src/sys/x86/isa/clock.c:409: warning: 'new_mode' may be used
uninitialized in this function

Could you have a look? Thanks.

-- 
Simon L. B. Nielsen