linux-user: Avoid redundant ENV_GET_CPU()

This fixes a mismerge in 874ec3c5b3821bb964f9f37b2f930f2a9ce51652.

Acked-by: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/linux-user/main.c b/linux-user/main.c
index 5dc0947..5309117 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -3637,7 +3637,7 @@
         exit(1);
     }
     cpu = ENV_GET_CPU(env);
-    cpu_reset(ENV_GET_CPU(env));
+    cpu_reset(cpu);
 
     thread_cpu = cpu;