avfilter/vf_v360: adjustment out_pad and in_pad maximum value to 1/10

Because not every user know about in_pad and out_pad reasonable value range
so maybe try to set 1.0, but setting 1.0 is so hugh to get an fatal error.
Suggested-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Steven Liu <lq@chinaffmpeg.org>

doc/filters.texi

@@ -18956,6 +18956,7 @@ No padding.
 @end table
 
 Default value is @b{@samp{0}}.
+Maximum value is @b{@samp{0.1}}.
 
 @item fin_pad
 @item fout_pad

libavfilter/vf_v360.c

@@ -133,8 +133,8 @@ static const AVOption v360_options[] = {
     {"out_forder", "output cubemap face order", OFFSET(out_forder), AV_OPT_TYPE_STRING, {.str="rludfb"},        0,     NB_DIRECTIONS-1, FLAGS, "out_forder"},
     {   "in_frot", "input cubemap face rotation",  OFFSET(in_frot), AV_OPT_TYPE_STRING, {.str="000000"},        0,     NB_DIRECTIONS-1, FLAGS, "in_frot"},
     {  "out_frot", "output cubemap face rotation",OFFSET(out_frot), AV_OPT_TYPE_STRING, {.str="000000"},        0,     NB_DIRECTIONS-1, FLAGS, "out_frot"},
-    {    "in_pad", "percent input cubemap pads",    OFFSET(in_pad), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,                 1.f,TFLAGS, "in_pad"},
-    {   "out_pad", "percent output cubemap pads",  OFFSET(out_pad), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,                 1.f,TFLAGS, "out_pad"},
+    {    "in_pad", "percent input cubemap pads",    OFFSET(in_pad), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,                 0.1,TFLAGS, "in_pad"},
+    {   "out_pad", "percent output cubemap pads",  OFFSET(out_pad), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},           0.f,                 0.1,TFLAGS, "out_pad"},
     {   "fin_pad", "fixed input cubemap pads",     OFFSET(fin_pad), AV_OPT_TYPE_INT,    {.i64=0},               0,                 100,TFLAGS, "fin_pad"},
     {  "fout_pad", "fixed output cubemap pads",   OFFSET(fout_pad), AV_OPT_TYPE_INT,    {.i64=0},               0,                 100,TFLAGS, "fout_pad"},
     {       "yaw", "yaw rotation",                     OFFSET(yaw), AV_OPT_TYPE_FLOAT,  {.dbl=0.f},        -180.f,               180.f,TFLAGS, "yaw"},