oss4 4.2-build2010-5ubuntu1~16.04.2 fails to build with x/linux-aws-hwe

[Kleber Sacilotto de Souza]

Testing failed on:
    amd64: https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-xenial/xenial/amd64/o/oss4/20181129_171135_4f839@/log.gz

[Kleber Sacilotto de Souza (kleber-souza)]

The dkms compilation is failing with the following error:

DKMS make.log for oss4-4.2-build2010 for kernel 4.15.0-1030-aws (x86_64)
Thu Nov 29 16:05:47 UTC 2018
make: Entering directory '/usr/src/linux-headers-4.15.0-1030-aws'
Makefile:975: "Cannot use CONFIG_STACK_VALIDATION=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel"
  CC [M] /var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.o
/var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.c: In function ‘oss_get_uid’:
/var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.c:476:23: error: dereferencing pointer to incomplete type ‘const struct cred’
   return current->cred->uid.val;
                       ^
/var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.c: In function ‘oss_timer_callback’:
/var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.c:518:3: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
   unsigned long id = tmout->id;
   ^
scripts/Makefile.build:332: recipe for target '/var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.o' failed
make[1]: *** [/var/lib/dkms/oss4/4.2-build2010/build/core/oss_core.o] Error 1
Makefile:1551: recipe for target '_module_/var/lib/dkms/oss4/4.2-build2010/build/core' failed
make: *** [_module_/var/lib/dkms/oss4/4.2-build2010/build/core] Error 2
make: Leaving directory '/usr/src/linux-headers-4.15.0-1030-aws'