ggml-hexagon: add HTP unary ops for ABS and LOG (#27786)

Add HVX-accelerated implementations for GGML_OP_LOG and
GGML_UNARY_OP_ABS on the HTP backend.

- Register HTP_OP_UNARY_ABS and HTP_OP_UNARY_LOG in op_remap_to_htp()
- Add ABS and LOG to ggml_backend_hexagon_device_supports_op()
- Implement hvx_abs_f32_aa() in hvx-arith.h using hvx_vec_abs_f32()
- Implement hvx_log_f32_aa() in hvx-log.h using hvx_vec_log_f32()
- Add abs_f32() and log_f32() row-wise dispatch in unary-ops.c
- Define tiled and non-tiled task functions via DEFINE_UNARY_TASK and
  DEFINE_UNARY_TILED_TASK macros
- Route HTP_OP_UNARY_ABS and HTP_OP_UNARY_LOG through execute_op()
  in main.c

ggml/src/ggml-hexagon/htp/htp-ops.h

@@ -62,6 +62,8 @@ enum htp_op_code {
     HTP_OP_UNARY_NEG,
     HTP_OP_UNARY_SOFTPLUS,
     HTP_OP_UNARY_TANH,
+    HTP_OP_UNARY_ABS,
+    HTP_OP_UNARY_LOG,
     HTP_OP_GLU_SWIGLU,
     HTP_OP_GLU_SWIGLU_OAI,
     HTP_OP_GLU_GEGLU,