lightnvm: merge gennvm with core

For the first iteration of Open-Channel SSDs, it was anticipated that
there could be various media managers on top of an open-channel SSD,
such to allow vendors to plug in their own host-side FTLs, without the
media manager in between.

Now that an Open-Channel SSD is exposed as a traditional block device,
there is no longer a need for this. Therefore lets merge the gennvm code
with core and simplify the stack.

Signed-off-by: Matias Bjørling <matias@cnexlabs.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/lightnvm/Makefile b/drivers/lightnvm/Makefile
index a7a0a22..b2a39e2 100644
--- a/drivers/lightnvm/Makefile
+++ b/drivers/lightnvm/Makefile
@@ -2,6 +2,5 @@
 # Makefile for Open-Channel SSDs.
 #
 
-obj-$(CONFIG_NVM)		:= core.o sysblk.o
-obj-$(CONFIG_NVM_GENNVM) 	+= gennvm.o
+obj-$(CONFIG_NVM)		:= core.o
 obj-$(CONFIG_NVM_RRPC)		+= rrpc.o