Remove broken sse_32 protokernels

[argilo]

volk_32fc_x2_conjugate_dot_prod_32fc fails in i386 Debian CI and locally. Only the a_sse_32 protokernel is broken:

108: offset 0 in1: 184.314 + -210.344j  in2: 183.667 + -210.042j tolerance was: 0.02
108: volk_32fc_x2_conjugate_dot_prod_32fc: fail on arch a_sse_32

I had a look over the code, and it appears the problem is that inline assembler writes to input, taps, and *result without telling the compiler about that. I made a few attempts at fixing it, but I'm not sure whether it's worth saving this ugly code. I doubt this protokernel sees much use, since it is only available on 32-bit systems, and many newer protokernels are now available on 32-bit x86.

It appears volk_32fc_x2_dot_prod_32fc_a_sse_64 had a similar bug, as it was commented out in 2012 and remains commented out today:

gnuradio/gnuradio@43224ac

I've removed that protokernel here as well. After this change, there are no more sse_32 protokernels left in VOLK.

[argilo]

I checked whether GNU Radio uses the volk_32fc_x2_conjugate_dot_prod_32fc kernel, and it only recently started doing so in gnuradio/gnuradio#3306. That's another good indication that the buggy volk_32fc_x2_conjugate_dot_prod_32fc_a_sse_32 protokernel hasn't seen any use.

[jdemel]

LGTM. Less assembly should improve maintenance as well. I wonder if this kernel is ever used nowadays.