use amalgamation build as default

This compiles the ktapvm as one huge C file and allows GCC
to generate faster and shorter code. Alas, this requires
lots of memory during the build.

Without amalg build:
[root@localhost ktap]# ll -h ktapvm.ko
-rw-r--r--. 1 root root 2.5M Nov 29 01:14 ktapvm.ko

With amalg build:
[root@localhost ktap]# ll -h ktapvm.ko
-rw-r--r--. 1 root root 1018K Nov 29 01:28 ktapvm.ko

Signed-off-by: Jovi Zhangwei <jovi.zhangwei@gmail.com>
rename kp_table_* to kp_tab_*

Signed-off-by: Jovi Zhangwei <jovi.zhangwei@gmail.com>