Set g_gmt_isset before calling gmtload() to prevent infinite recursion.
When CONFIG_SYSLOG_TIMESTAMP is enabled, syslog calls gmtime_r() to
format timestamps. gmtime_r() -> gmtsub() -> gmtload() -> tzload()
tries to open the timezone file. If the file doesn't exist on romfs,
romfs_open() calls ferr() which expands to syslog(), causing infinite
recursion since g_gmt_isset is still 0.
By setting g_gmt_isset = 1 before gmtload(), any recursive syslog
call during timezone loading will skip the gmtload path and use the
partially initialized state for timesub(), avoiding stack overflow.
Signed-off-by: ligd <liguiding1@xiaomi.com>
0ce2d3f59a