RCU: make treercu be default
RCU: make treercu be default

Impact: switch default config from CLASSIC_RCU to TREE_RCU

Given that I have not gotten any complaints or bug reports on treercu
recently, this patch makes it be the default.  There are a number of
other defconfig files that explicitly call out CLASSIC_RCU, but which
have comment headers saying not to edit them.  Probably holdovers from
one of the flavors of "make config", but...

Signed-off-by: Paul E. McKenney <1e0ce936bb9b355d257bf5790d2513c3f28be22b@linux.vnet.ibm.com>
Cc: 5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org
Cc: a6f1be4247cea11e3150b15872843079f20d7078@in.ibm.com
Cc: a103ef9226f51cd1e5e835b2f74c82dfb33d1ccb@us.ibm.com
Cc: e4eddfaff1fc5d7affa656f47ee4d83207ccac30@colorfullife.com
Cc: 3fddac958924aef220f202ca567388ddab3f14a8@infradead.org
LKML-Reference: <9712813d460eea41de1b854d5daa8b7046a57a6f@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <9dbbbf0688fedc85ad4da37637f1a64b8c718ee2@elte.hu>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas