Fix parsing of <MULTIPLE> breakpoints.

Fix parsing of <MULTIPLE> breakpoints.

When a breakpoint is set in a template function that is instantiated more
than once, then GDB inserts a breakpoint in each instance. The breakpoint
list looks like this:

Num     Type           Disp Enb Address            What
1       breakpoint     keep y   <MULTIPLE>
1.1                         y     0x0000000000400b94 in Templated<int>::Templated(int) at multibrkpt.cpp:9
1.2                         y     0x0000000000400c14 in Templated<double>::Templated(double) at multibrkpt.cpp:9

KDbg parses this list somehow, but it does not recognize the multiplicity
of the breakpoint; it keeps a breakpoint record for each of the lines. This
eventually grows the breakpoint list each time the session is loaded.

Fix the parser to understand these breakpoints. Location information is
filled in from the first real breakpoint instance.