Made the constant following the "interrupt" keyword optional. If omitted,

Made the constant following the "interrupt" keyword optional. If omitted,
the function will not automatically be given an entry in the interrupt
vector table (similar to #pragma NOIV, but less syntacticly kludgy). The
interrupt number is also now range checked.

* src/SDCC.y
* src/SDCCmem.c
* src/SDCCglue.c
* src/SDCCsymt.h
* support/Util/SDCCerr.c
* support/Util/SDCCerr.h
* doc/sdccman.lyx

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@2823 4a8a32a2-be11-0410-ad9d-d568d2c75423