fstab.shamu: Don't use "discard" option on userdata

Mount userdata without discard, let FI_TRIM work instead.

Bug: 18151232
Change-Id: I1df050fd09a9b0ba82c961aeb61961fd43833caa
diff --git a/fstab.shamu b/fstab.shamu
index 83c4af9..3986190 100644
--- a/fstab.shamu
+++ b/fstab.shamu
@@ -7,7 +7,7 @@
 
 #<src>                                                <mnt_point>  <type>  <mnt_flags and options>                     <fs_mgr_flags>
 /dev/block/platform/msm_sdcc.1/by-name/system         /system      ext4    ro,barrier=1                                wait
-/dev/block/platform/msm_sdcc.1/by-name/userdata    /data        ext4    rw,discard,nosuid,nodev,noatime,nodiratime,noauto_da_alloc,nobarrier    wait,check,forceencrypt=/dev/block/platform/msm_sdcc.1/by-name/metadata
+/dev/block/platform/msm_sdcc.1/by-name/userdata    /data        ext4    rw,nosuid,nodev,noatime,nodiratime,noauto_da_alloc,nobarrier    wait,check,forceencrypt=/dev/block/platform/msm_sdcc.1/by-name/metadata
 /dev/block/platform/msm_sdcc.1/by-name/cache       /cache       ext4    rw,noatime,nosuid,nodev,barrier=1,data=ordered   wait,check
 /dev/block/platform/msm_sdcc.1/by-name/modem       /firmware    ext4    ro,barrier=1,context=u:object_r:firmware_file:s0    wait
 /dev/block/platform/msm_sdcc.1/by-name/boot         /boot           emmc    defaults                                                        defaults