perf scripts python arm-cs-trace-disasm.py: Set start vm addr of exectable file to 0

perf scripts python arm-cs-trace-disasm.py: Set start vm addr of exectable file to 0

For exectable ELF file, which e_type is ET_EXEC, dso start address is a
absolute address other than offset. Just set vm_start to zero when dso
start is 0x400000, which means it is a exectable file.

Reviewed-by: James Clark <james.clark@arm.com>
Signed-off-by: Ruidong Tian <tianruidong@linux.alibaba.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Grant <al.grant@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Tor Jeremiassen <tor@ti.com>
Link: https://lore.kernel.org/r/20231214123304.34087-3-tianruidong@linux.alibaba.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>