Closes #14 - Restore support for kernel module versioning
patches/kernel-4.19-cs/config-4.19.67-cs - change to MODVERSIONS=y
patches/kernel-4.19-cs/README - Update note on config file
-- changes for mbuf, gpstime symbol versions --
Update RCG autotools - remove configure, move configure.in to configure.ac
bootstrap - add to generate configure from configure.ac
configure.ac - rename from configure.in, add tests to find path to mbuf, gpstime
Module.symvers files - either /var/lib/dkms/$MODNAME/$MODVERS/$KVERS/$ARCH/
for DKMS package or /var/cache/$MODNAME from local build
src/drv/ExtraSymbols.symvers - Remove mbuf, gpstime symbols
src/drv/gpstime/Makefile - Add caching of Module.symvers in /var/cache/gpstime on install
src/drv/mbuf/Makefile - Add caching of Module.symvers in /var/cache/mbuf on install
src/epics/util/Makefile.in  - Add mbuf,gpstime Module.symvers paths
src/epics/util/feCodeGen.pl - Add KBUILD_EXTRA_SYMBOLS statements to front-end make file
-- changes to ...

Closes #15 Remove kernel patch changing cpu_up to EXPORT_SYMBOL
Update README in patches/linux-4.19-cs for change
Remove symbols from patched kernel in src/drv/ExtraSymbols.symvers
Add parameter in GNUmakefile to build will reference Module.symvers from kernel

Disable CONFIG_DRM_AST flag so kernel uses 'nomodeset' on AST VGA chips
which prevents interrupts causing long IOP cycles on newer front-ends
(and removes need for nomodeset as kernel boot parameter)
Update README in patches/linux-4.19-cs for these changes