util/cbfstool: Fix linux_trampoline.c generation

linux_trampoline.c generation is broken with latest crossgcc-i386
toolchain. Fix the issue to enable the building.

../cbfstool/linux_trampoline.S: Assembler messages:
../cbfstool/linux_trampoline.S💯 Error: no instruction mnemonic
	suffix given and no register operands; can't size
	instruction
<builtin>: recipe for target '../cbfstool/linux_trampoline.o'
	failed

TEST=Build and boot on intel/archercity CRB

cd util/cbfstool/
rm linux_trampoline.c
make linux_trampoline.c

Change-Id: I7faca296f946bb4e9fd510661357925e5dcf9a6b
Signed-off-by: Shuo Liu <shuo.liu@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82704
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

util/cbfstool/linux_trampoline.S

@@ -97,7 +97,7 @@ je .endScan
 cmp $12, 16(%edi) /* type */
 jng .next_e820_entry
 /* Fixup the type to 2, reserved memory */
-mov $2, 16(%edi)
+movl $2, 16(%edi)
 .next_e820_entry:
 dec %eax
 add $20, %edi