MAINTAINERS: update FPU EMULATOR web page

The web page entry for the FPU EMULATOR no longer works.  I notified Bill
of this and he asked me to update it to this new entry.

Link: https://lkml.kernel.org/r/20230214170208.17287-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Bill Metzenthen <billm@melbpc.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Author: rddunlap

MAINTAINERS

@@ -8196,7 +8196,7 @@ F:	drivers/fpga/microchip-spi.c
 FPU EMULATOR
 M:	Bill Metzenthen <billm@melbpc.org.au>
 S:	Maintained
-W:	http://floatingpoint.sourceforge.net/emulator/index.html
+W:	https://floatingpoint.billm.au/
 F:	arch/x86/math-emu/
 
 FRAMEBUFFER CORE