Finally solved it.  The GIER register is 0x10.  However the the I2C interface to the WK2132 chip uses only the bottom four bits of the register number.  To set/read GIER and GIFR you need to set the C0 bit in the device address to 1.

After more tests, I never see any bits set in the GIFR register, even when bits are get in the SIFR register.  That probably explains why the IRQ line never changes, but why is GIFR not set?  I am missing some initialization?

Any help appreciated, my project is totally blocked until I can resolve this!